Authorities are investigating a series of fires set in and around a Seattle homeless encampment along Interstate 5 known as the Jungle.

The Seattle Fire Department said on Twitter investigators have determined that eight fires, including one in a vacant building Monday afternoon, were intentionally set.

Seattle Police Capt. Paul McDonagh said Monday evening five initial fires were started with three blazes spotted later in the day, prompting a large police response and search for a suspect.

The fires closed a portion of Dearborn Street for hours while firefighters extinguished the blazes.

Seattle police also changed the suspect's description to a white man in his 30s, 5 foot 6 inches tall with short hair and possibly a Mohawk. Police said he was described as wearing black shorts and no shirt.

Anyone who sees him should call 911.