FLAT ROCK (WWJ) – It may be a clue into what happened to a woman who went missing last Halloween in Monroe County.

Police searching for missing Chelsea Bruck combed a field in Flat Rock near Vreeland and Peters roads on Sunday and discovered clothing which may be similar to a Halloween costume that Bruck was wearing the night she disappeared.

READ MORE: Michigan Reports 7,733 New COVID-19 Cases, 35 Deaths

“Detectives searched an abandoned industrial site consisting of approximately 60 overgrown acres, formerly known as Specialty Petroleum,” police said in a statement. “Detectives … executed a search warrant and collected clothing and other evidence related to Chelsea Bruck. The collected items were sent to the Michigan State Police Crime Lab for forensic analysis.”

Investigators are testing the clothing for DNA evidence in hopes there may be information they can use.

Bruck was last seen dressed in a “Poison Ivy” Batman costume with black yoga pants, green ivy leaf-covered shirt and a long dark purple wig.

Cassandra Bruck, Chelsea’s sister, says the field is not too far from where the party took place.

“They are asking that everyone stay away and let them do their job,” said Cassandra Bruck. “We are just going about our day and obviously we have our phones on – waiting for any news and you kind of learn over five months that you can’t just sit and wait – whatever we had planned – keep going.”

Cassandra said she is hopeful that her sister is still alive. “Very hopeful that she’s still alive, we’ll find her and she’ll be able to come home.”

READ MORE: Fall Hayrides Begin Oct. 1 At Heritage Park In Farmington Hills

Bruck was at a party on October 25 at a Newport, Michigan farmhouse, about eight miles from her home.

According to a witness Bruck left the party with an unknown white male.

Chelsea Bruck, was last seen wearing this Poison Ivy costume. -- A composite image of a man who may have been seen with Chelsea Bruck.

Chelsea Bruck, was last seen wearing this Poison Ivy costume. — A composite image of a man who may have been seen with Chelsea Bruck.

The person of interest is described as a male of medium build, with medium-length dark hair, a thin mustache and some facial hair.

He was wearing a plain, black hooded sweatshirt with no visible logo and black-framed glasses.

Bruck is described as a blonde-haired white female, around 5-feet-7 inches tall. She is reportedly 140 pounds and has a small tattoo of an anchor behind her right ear.

Family members have put out t-shirts, fliers, even billboards, in an effort to find Bruck.

MORE NEWS: Ballot Drive: Join Michigan With National Popular Vote Pact

Investigators say it may be a while before they know whether the clothing discovered in Flat Rock is related to her disappearance.