The carcass of the cougar has been sent for examination by officials at Washington State University in Pullman. The animal was stalking the cyclists and was acting abnormally, Fish and Wildlife officials said. 
 
 The cougar that attacked two bicyclists near North Bend on Saturday, killing one and leaving the other with serious injuries, was “emaciated,” according to a fish and wildlife official. 
 
 Capt. Alan Myers, of the state Department of Fish and Wildlife police, said the brain of the 100-pound cat will be tested to determine why it attacked the cyclists, the first fatal encounter between a human and a cougar in the state in nearly a century. 
 
 Myers said the carcass of the cougar was transported Sunday to Washington State University in Pullman, where a veterinarian will conduct a brain necropsy to determine if the cougar was sick. Cougar attacks on humans are extremely rare. 
 
 Myers confirmed the identities of the victims as S.J. Brooks, 32, of Seattle, and injured friend Isaac Sederbaum, 31, also of Seattle. The King County Medical Examiner’s Office will formally identify the victim after an autopsy is performed. They were mountain biking on a remote, dirt road northeast of Snoqualmie on Saturday morning when they came across the cougar, which began stalking them and then attacked, according to police and Fish and Wildlife officials. 
 
 Sederbaum suffered serious lacerations and bites to his head, neck and face, requiring surgery. He’s in satisfactory condition at Harborview Medical Center, according to spokeswoman Susan Gregg. 
 
 Brooks was the director of operations at Hillman City Collaboratory, where grass-roots organizations and people share the space, and was a research assistant at William James College in Massachusetts. A Linked-In profile also states Brooks had been the office manager of G&O Family Cyclery in Seattle’s Greenwood neighborhood. While living in the Boston area, Brooks was a manager at Boston Center for the Arts and a bicycle mechanic. According to the profile, Brooks got a doctorate in the history of art and architecture at Boston University in 2016. 
 
 Tom Fucoloro, founder of Seattle Bike Blog, wrote a story about Brooks who had started a Seattle chapter of Friends on Bikes to help women of color, trans and non-conforming people become interested in bicycling. 
 
 While cougar attacks on people are not unheard of, this animal’s behavior was very abnormal, Myers said. Initially, the cougar started to chase them down the road. They stopped, made noise and one of them swung a bike at it in an attempt to distract and frighten it, which is what’s recommended during encounters. The animal appeared to have left, he said, but, instead, it circled back and pounced on Sederbaum’s head. 
 
 “The cougar had his head in his jaws and was shaking him violently,” Myers said. 
 
 Brooks dropped the bike and ran into the woods. The cougar abandoned its attack on Sederbaum and went after Brooks. 
 
 “You are in a flight or fight situation – you are going to want to flee and it’s completely natural but it triggers a chase response in a cougar,” Myers said. 
 
 Sederbaum, bleeding and seriously injured, rode two miles before he was able to find cellphone coverage and call 911. 
 
 Myers described the animal — which was treed by dogs and shot a few hours later not far from the site of the attack — as an “emaciated” 3-year-old, 100-pound male. “It was skinnier than normal,” he said. Males that age typically weigh upward of 140 pounds, according to the Department of Fish and Wildlife website. 
 
 Law enforcement found Brooks’ body had been dragged and partially concealed under a log near the gravel road. The cougar was on top of the body when officials first arrived. 
 
 Myers said Brooks was severely mauled, with wounds to the legs, head, face and neck. 
 
 While cougars are very common in the foothills of the mountains, attacks are rare. The last fatal attack in Washington was in 1924, when a cougar ambushed a teenage boy near his home in Olema, Okanogan County. Since then, there have been 18 nonfatal attacks in the state. There were nine cougar attacks in the 1990s, Myers said. 
 
 Normally, cougars are secretive and aloof, said Myers, who has encountered many of them and has not felt threatened. They hunt and eat deer, elk, rabbits and small critters in the early morning, at dusk and evening. 
 
 Males are solitary. On average, an adult male weighs 140 pounds, with females about 25 percent smaller. They have exceptionally powerful legs that enable them to leap 30 feet from a standstill, according to the Department of Fish and Wildlife. 
 
 Rich Beausoleil, the state’s bear and cougar specialist, said that cougars are territorial, and they limit their own population growth to about two cougars per 39 square miles. 
 
 Cougars, also known as mountain lions and pumas, are a protected species. Each year, the state allows 250 cougars to be hunted and killed in 50 designated zones. 
 
 Seattle Times news producer Jeff Albertson contributed to this report. 
 
 Correction: Information in this article, originally published May 20, 2018, was corrected May 25, 2018. Due to erroneous information from the state Department of Fish and Wildlife, a previous version of this story incorrectly stated that there had been 15 nonfatal cougar attacks in Washington state in the past century, with seven of them coming in the 1990s. There have been 18 nonfatal cougar attacks in the past century, with nine in the 1990s. 

 Washington State Fish and Wildlife Police confer with an individual from the King County Medical Examiner's and a King County Sheriff's deputy on a remote gravel road above Snoqualmie, WA., following... (Associated Press) 
 
 Washington State Fish and Wildlife Police confer with an individual from the King County Medical Examiner's and a King County Sheriff's deputy on a remote gravel road above Snoqualmie, WA., following a fatal cougar attack. Saturday May 19, 2018. One man was killed and another seriously injured when... (Associated Press) 
 
 SEATTLE (AP) — The two mountain bikers did what they were supposed to do when they noticed a mountain lion tailing them on a trail east of Seattle. 
 
 They got off their bikes. They faced the beast, shouted and tried to spook it. After it charged, one even smacked the cougar with his bike, and it ran off. 
 
 It wasn't enough, authorities said. 
 
 As they stood trying to catch their breath, the cougar returned, biting one of them on the head and shaking him, Capt. Alan Myers of the Washington Department of Fish and Wildlife Police said Sunday. 
 
 The second cyclist ran, and the animal dropped the first victim and pounced on him, killing him and dragging him back to what appeared to be its den. 
 
 "They did everything they were supposed to do," King County sheriff's Sgt. Ryan Abbott said. "But something was wrong with this cougar." 
 
 The attack Saturday near North Bend, in the Cascade Mountain foothills 30 miles (48 kilometers) east of Seattle, was the first fatal cougar attack in the state in 94 years. Myers said Sunday that the cougar was underweight — about 100 pounds (45 kilograms), when a typical 3-year-old male in the area would be 140 to 180 pounds (63 to 81 kilograms). 
 
 The 31-year-old Seattle man who was bitten first, Isaac Sederbaum, survived. Rescuers flew him to a hospital, where he was in satisfactory condition Sunday, Harborview Medical Center spokeswoman Susan Gregg said. 
 
 Myers identified the deceased victim, a 32-year-old Seattle resident, as S.J. Brooks. 
 
 After the cougar attacked Brooks, a badly bloodied Sederbaum managed to get on his bike and ride off. He rode for 2 miles (3 kilometers) before he could get a cellphone signal to call 911. 
 
 When rescuers arrived, it took about half an hour to find Brooks, who was dead with the cougar on top of him in what appeared to be a den-like area. An officer shot at it, and it ran off. Several hours later, Washington Department of Fish and Wildlife agents used dogs to track it to a nearby tree. They shot and killed it. 
 
 Authorities plan to match DNA taken from the animal with DNA from the victims to be certain they killed the right cougar. They sent the animal's carcass to a veterinary lab at Washington State University for a necropsy to determine what might have been wrong with it. 
 
 There are an estimated 2,000 cougars in Washington. Until the 1960s, the state paid hunters a bounty for killing them. Now, it allows 250 to be hunted in 50 designated zones. 
 
 While they are sometimes known to kill livestock or pets, and though one even found its way into a park in Seattle in 2009, encounters with people in Washington state are rare. 
 
 Attacks have become more common as people increasingly encroach on the animals' territory. In North America, there have been about 25 deadly attacks and 95 nonfatal attacks reported in the past century, but more attacks have been reported in the U.S. West and Canada over the past 20 years than in the previous 80, according to Fish and Wildlife. 
 
 Experts say that people encountering the big cats in the wild should stop and pick up small children immediately. Because running and rapid movements can trigger the animal's prey drive, don't run. Instead, face the cougar, speak firmly and slowly back away — appearing as large as possible, such as by standing on a rock or stump or opening a sweatshirt or jacket. 
 
 Keep your eyes on the animal and become more assertive if it doesn't back off. And if it does attack, fight back. 
 
 "The idea is to convince the cougar that you are not prey, but a potential danger," Fish and Wildlife advises on its website.
– "They did everything they were supposed to do. But something was wrong with this cougar." That's the take from King County Sheriff's Sgt. Ryan Abbott after a rare attack on humans left one cyclist dead in Washington state Saturday and another badly injured. The Seattle men's identities have been released; SJ Brooks, 32, was killed and Isaac Sederbaum, 31, was injured. Police say the 3-year-old cougar, which was located and killed after the attack, was "emaciated," weighing just 100 pounds rather than the more typical 140 to 180 pounds. "It was skinnier than normal," says state wildlife official Alan Myers. A brain necropsy will be performed to see whether the animal was sick, the Seattle Times reports. Officials say the animal acted abnormally; cougars don't often attack humans, and the last fatal cougar attack in Washington occurred in 1924. The cougar chased the men down the road; they got off their bikes and followed recommendations for facing down a cougar: yelling at it in an attempt to scare it away, and hitting it with one of the bikes when it approached. It ran off, but as the men tried to catch their breath, it circled back and grabbed Sederbaum by the head, the AP reports. "The cougar had his head in his jaws and was shaking him violently," Myers says. Brooks dropped his bike and ran, causing the cougar to let go of Sederbaum, chase Brooks down, pounce on him, and kill him. "You are in a flight or fight situation—you are going to want to flee and it’s completely natural but it triggers a chase response in a cougar," Myers says. The animal dragged Brooks to its apparent den as Sederbaum rode to find cell reception and call for help. (In California, cougars have acquired a taste for pets.)