The other driver, Carmen Myers, 32, of 42 N. Decatur St., Strasburg, is being charged with an unsafe lane-change violation. It is a summary offense that has a base fine of $25.

Michael E. Kling, of 152 Strasburg Pike, was killed Jan. 8, and 20 Conestoga Valley elementary school students and their bus driver suffered minor injuries, after Kling's pickup truck veered into the oncoming path of the bus.

The 7:59 a.m. accident happened in the 2000 block of Lincoln Highway East, between Wal-Mart and Pep Boys.

Police initially said they did not know what caused Kling's truck to swerve suddenly into the oncoming lane and strike the left, front side of the bus, which was carrying 38 students from Smoketown and Fritz elementary schools.

But their investigation revealed that Myers inadvertently caused the accident, they said today.

Myers was traveling the same direction, eastbound, as Kling on the morning of the crash, said East Lampeter Township police Lt. Robin Weaver. She was in the right lane and Kling was in the left lane. The bus was going west, in the left lane.

Myers wanted to get in the left eastbound lane, to get onto the Route 30 bypass.

"She made a lane change in an unsafe manner,'' Weaver said.

"She maneuvered into the left lane, in front of the Kling vehicle. He took evasive action that precipitated his crossing the center line into the oncoming lane.''

"It wasn't intentional,'' Weaver added. "It was just too close and unsafe.''

Myers remained at the accident scene after the collision and gave police a statement about what happened, Weaver said.