HAYWARD, Calif. -- The man whose body was found on the southbound lanes of Interstate Highway 880 in Hayward on Thursday has been identified by the Alameda County coroner's bureau as 37-year-old David Connolly of Berkeley.

The coroner's bureau said they recovered part of one hand and most of another and were able to lift fingerprints.

Witnesses reportedly told California Highway Patrol officers that Connolly was trying to hitchhike from Berkeley to Hayward. A truck driver pulled over but refused to give the man a ride.

Witnesses said Connolly then walked to the back of the truck and, without the driver's knowledge, grabbed onto the back.

Connolly held on for as long as possible but eventually lost his grip and fell into the roadway. The coroner's bureau said he was struck about 20 times and died of multiple blunt force trauma.

The CHP had reported that Connolly was Hispanic, but he is white, according to the Alameda County coroner's bureau.

The discovery of Connolly's body parts spread across Highway 880 early Thursday ground the southbound commute on the busy corridor in San Francisco's East Bay to a halt for more than two hours, backing up traffic for miles.

The California Highway Patrol originally reported that an animal had been hit and dismembered on the freeway between West A Street and West Winton Avenue in Hayward in the predawn hours, but closer examination when the sun came up around 7 a.m. revealed that the body parts were human.

CHP officers had the gruesome task of spreading out across the freeway to mark the body parts for the coroner. A tennis shoe surrendered by a spray-painted circle was a grim reminder of the accident's toll.

The southbound lanes were immediately closed once the remains were identified, forcing thousands of cars to exit onto city streets backing up traffic for miles. The CHP reopened all four lanes of the freeway by 9:45 a.m., relieving the traffic bottleneck while continuing their roadside investigation.