Police investigating the Idaho quadruple murder say they found a "possible animal hair strand" inside alleged killer Bryan Kohberger's home, and cops think it could be a direct connect to the site of the slayings.
A search warrant for Kohberger's home, obtained by TMZ, says police seized several other notable items from the raid ... including items with dark red and brown stains.
The search warrant notes there was a significant amount of blood spilled in the murder house, with investigators saying they believe the killer would have blood evidence on their body or clothing.
Police were looking for trace evidence of blood stains in Kohberger's apartment, and the docs say there was a pillow with a "reddish/brown stain" and an item with a "collection of dark red" spotting.
The hair strand could be huge -- there was a dog in the students' home at the time of the murders, and the killer spared the pooch. According to the docs, cops went looking for hair at Kohberger's apartment, and found the possible animal hair ... as well as strands from humans.