WESTMORELAND, N.H. – A driver who crashed into a group of motorcyclists on a memorial ride in New Hampshire, killing two of them, couldn’t explain why he crossed the center line and drove head-on into the procession, police said.

More than 200 motorcyclists were riding in Westmoreland on Saturday morning when a car driven by 87-year-old Robert Lockerby of Walpole swerved into their lane and struck seven of them.

The collision killed 59-year-old Gary Champney of Alstead and 41-year-old Aaron Robar of Newport. Five others were injured.

When police arrived, the scene was chaotic and there was a general feeling that the accident had happened “in a flash,” Trooper Sean Eaton said Saturday. Lockerby couldn’t shed any light on exactly what had happened, he said.

“Basically, he was unable to offer a reason for the crash,” he told WMUR-TV.

The annual Ride for the Fallen is held in honor of Army Spc. Justin Rollins, a Newport native who was killed in Iraq by a roadside bomb in 2007. The ride raises money for local high school students.

Police are investigating the accident but said alcohol and speed do not appear to be factors.

Rollins’ parents, Rhonda and Skip Rollins, were among those participating in Saturday’s ride. The crash happened directly in front of the car in which Rhonda Collins was riding, Eaton said.

Mike Hammond, one of the ride organizers, said people are looking for answers.

“Only the Lord knows why this happened,” he wrote in an email.