Lawrence police and medics respond to a wreck reportedly involving a motorcycle and a car near Iowa Street and University Drive on Wednesday, August 31, 2011.

A man died Wednesday in a rush-hour accident that shut down one of the city’s main thoroughfares for hours.

The accident at 6:15 p.m. Wednesday involved a motorcycle and a van near Iowa Street and University Drive, said Sgt. Matt Sarna, a Lawrence police spokesman.

Sarna said according to a preliminary investigation, it appeared the motorcyclist, headed northbound, veered into the lanes of oncoming traffic and was struck by the southbound van. Lawrence-Douglas County Fire Medical workers declared the motorcyclist dead at the scene, and no other injuries were reported.

“We believe that he was slowing for traffic and went into the other lane and got hit then,” Sarna said.

Iowa Street was closed in both directions between 15th Street and Stratford Road until just before 11 p.m. Wednesday as police investigated the crash. It caused major traffic headaches Wednesday evening in area neighborhoods near the Kansas University campus.

Police Wednesday night did not identify the motorcyclist, pending notification of family members. Sarna also did not release the man’s age or hometown.

A Lawrence-Douglas County Fire Medical supervisor initially asked about the availability of a helicopter ambulance, but it was later called off. The crash occurred on one of the city’s busiest streets.

“For any kind of vehicle during the rush hour, it’s always going to be busy, and we always tell people to drive carefully,” Sarna said. “In some instances they just need to be more aware of their surroundings when they’re driving. In this instance we’re not sure exactly what happened, so we can’t be as sure until we go through the whole investigation process.”

This is the second fatality in Lawrence in recent days after a Michigan man, who was possibly involved in a chase with a Tonganoxie police officer earlier, died in a North Lawrence crash early Saturday morning.