text: Police searched an area near a Ford Motor Company plant in Michigan on Sunday for clues related to the disappearance of a woman who was last seen at Halloween wearing a Poison Ivy costume . Chelsea Ellen Bruck, 22, has been missing almost six months, police said. Monroe County Sheriff's Major Jeff Kemp reported that the search was arranged after investigators received a tip from a citizen about the area in Flat Rock. 'All I can say … is we're looking for evidence,' the sheriff's office said. He declined to discuss media reports that part of Chelsea's costume were found. Scroll down for video . A new search was conducted on Sunday in the case of missing Chelsea Ellen Bruck, 22, who was last seen dressed as Batman villain Poison Ivy at a Halloween party on October 25 attended by around 800 people . Miss Bruck, 22, from Maybee has not been seen since the early hours of October 26, 2014 despite extensive searches on foot and by helicopter to locate her . The Maybee woman was dressed as the comic villain Poison Ivy when she attended a Halloween party October 26 in Frenchtown Township. The costume included a leaf-covered top and dark purple wig. That was the last time she was seen at the outdoor party at a rural farmhouse which was attended by around 800 people, 35 miles southwest of Detroit. Her mother, Leannda Bruck, told AP that detectives were actively working on the case but declined to say anything else. Sheriff's deputies and Flat Rock police conducted the search on Sunday night focusing on an area near the Flat Rock Assembly Plant. Daily Mail Online was awaiting a comment from the Flat Rock police department on Monday. Jennifer Bruck, left, prays for sister Chelsea with parents Matt and Leannda Bruck and other family and friends who turned to public prayer in Monroe, Michigan last October. She has not been seen for six months . Police have interviewed multiple people and investigated hundreds of tips over the past six months. A witness reported seeing Miss Bruck walking about 3am with a man as the party was winding down.The sheriff's office published a sketch of the man she was seen with in a parking lot. The dark-haired man had thin stubble and wore glasses with a black hoodie. The man has not been identified and police have not named him as a suspect. Two were charged separating for telling police lies about the missing woman. In a missing person appeal, Chelsea Bruck is described as 5'7' tall, 140lbs, blonde, with a small anchor tattoo behind her right ear. She was last seen wearing black yoga pants, a black wig and a leaf-covered vest. Anyone with information about the case is asked to call the Monroe County Sheriff's Office at (734) 240-7700 or Monroe County Central Dispatch at (734) 243-7070. Authorities released this sketch of the man Miss Bruck was seen with in a parking lot around 3am following a party in Frenchtown Township, Michigan just before Halloween . Her sister, Kassandra Bruck, 24, told the Detroit Free Press last year that the family is encouraging people to share photos of Chelsea - across Michigan and beyond. She told NBC: 'This is 100% uncharacteristic, it's not anything she would do. She even told my mom, ''I'm not staying long. I'll be back in a couple of hours.'' This has just broken my parents.' Ms Bruck told CBS on Monday that she was 'very hopeful' her sister would be found alive. The party host Mike Williams, 30, told the paper he had been forced to close the party, intended for 500 people, after around 800 revelers turned up. He added that he hadn't seen Miss Bruck at the party at all. A GoFundMe campaign to help find Miss Bruck has raised close to $9,000. Missing posters offered a close-up of an anchor-shaped tattoo behind Miss Bruck's right ear .
target: Chelsea Ellen Bruck, 22, was last seen in the early hours of October 26 in Frenchtown Township, Michigan dressed as the Batman villain Poison Ivy .
  Police searched an area near a Ford Motor Company plant in Michigan .
  The sheriff's office declined to discuss media reports that part of Chelsea's costume were found .
  She was last seen in the parking lot with dark-haired man at 3am .
  The party had to be shut down after numbers swelled from 500 to 800 people .