Pedestrian struck by school bus in Derwood, Md. (Courtesy of Montgomery County Fire and Rescue)

A Montgomery County Public School bus struck and killed a pedestrian Thursday morning in the Derwood area.

Crucita Reynoso, 58, of Gaithersburg was killed in the crash, which happened around 9 a.m. near the intersection of Redland Road and Crabbs Branch Way.

Bus driver Jonathan Chinghun Chiu, 54, of Gaithersburg was making a left turn as Reynoso was crossing the road, police said. The cause of the crash is under investigation.

Montgomery County police and school officials said there were no schoolchildren aboard the bus at the time of the incident.

Montgomery schools spokesman Dana Tofig said the bus had finished its morning run and was headed back to a school district bus depot when the incident occurred.

Julie Zauzmer contributed to this report.