Smith also said that Nassau County Police would be coordinating with Suffolk County and New York State Police on the investigation. Five days later, the search for more bodies began in Nassau County. An additional set of partial human remains was found, as well as a separate skull, bringing the potential total number of victims found since December to ten. On April 22, two human teeth were found about a foot from the skull. On June 16, 2011, Suffolk County police raised the reward from $5,000 to $25,000 (the largest offered in the county's history) for information leading to an arrest in the Long Island murders. On September 20, police released composite sketches of two of the unidentified victims whose remains were found in March and April (an Asian male and Jane Doe No. 6), as well as photos of jewelry found on the remains of a female toddler and her mother, found on April 4 and 11, respectively. The toddler's mother was reported as one of the sets of remains found in Nassau County on April 11. Also on September 20, police revealed that the second set of remains found in Nassau County on April 11 matched two legs found in 1996 in a garbage bag that had washed up on Fire Island. , the police had received over 1,200 tips via text, email and phone since the beginning of the investigation. On November 29, 2011 police announced that they believed one person is responsible for all 10 murders, and that the person is almost certainly from Long Island. The single killer theory was related to common characteristics among the condition and forensic evidence related to the bodies. On December 13, 2011, police announced that the remains of Shannan Gilbert were found in a marsh about half a mile from where she had disappeared. A week earlier, they had found some of her clothes and belongings in the same vicinity. Police believe that Gilbert accidentally drowned after stumbling into the marsh. Her mother disagrees. Gilbert was last seen banging on a resident's door and screaming for help before running off into the night. Gilbert made a 9-1-1 call that night, saying she feared for her life. On December 10, 2015, Suffolk County Police Commissioner Tim Sini announced that the FBI had officially joined the investigation. The day before, former Police Commissioner James Burke, who resigned in October, had been indicted for alleged police brutality and other issues. He was said to have blocked FBI involvement in the LISK cases for years. A spokesperson for the FBI confirmed their official involvement. The FBI had previously assisted in the search for victims, but was never officially part of the investigation.