LAWRENCE | Police said they found the source of an oil spill which caused a minor two-car accident by following oily tire tracks to a parked truck.

The two cars collided at Berkeley and Fern streets about 1:30 p.m. yesterday and when police arrived, they discovered the road was made slick due to what appeared to be an oil spill.

Police Lt. Daniel Fleming, day shift commander, said officers responding to the scene followed the tire tracks about a half-mile to 193 Bruce St. where they found a 1978 GMC box truck owned by Angel Rosario, 48.

Fleming said Rosario told police he had removed an old boiler from a home on Market Street and poured the oil from the boiler into a plastic barrel, then put the barrel and the boiler into the back of the truck.

Police said Rosario then drove the truck to a Haverhill scrap yard and sold the boiler there.

Rosario drove the truck back to Lawrence, and when he hit the incline on Fern Street, the barrel of oil tipped over, spilling the oil inside the truck and onto the roadway, causing the accident, Fleming said.

According to the police report, the oil spill started at Bruce Street, went to Berkeley, continued up to Swan Street and extended at the intersection of Berkeley and Fern to the intersection of Lexington Street.

" The entire roadway was covered in the oil substance," Officer Stacey Griffin wrote in his report.

The quantity of oil spilled was not immediately known, but "it was a big mess," Fleming said.

Fleming said Detective Daron Fraser was attempting to determine the address from where the boiler was removed, adding that police don't believe it was taken from an abandoned building.

No one was injured in the crash.

Rosario was cited by the Massachusetts State Police truck team for having no placards on the truck, package not secured in a vehicle, and inadequate brakes for safe stopping, Fleming said.

Public works crews sanded the streets in the area, which were closed as a result of the oil spill. The city may attempt to bill Rosario for the cleanup.