A Montgomery County school bus struck and critically injured a bicyclist Wednesday afternoon in the Darnestown area, county officials said.

The accident happened on Darnestown Road, near Berryville Road, about 2:30 p.m., said Officer Janelle Smith, a police spokeswoman. The cyclist, who was identified only as a male, was taken to a hospital with life-threatening injuries, Smith said. 

The school bus had students on board but they were not injured, said Asst. Chief Scott Graham, a county fire department spokesman. The bus driver was taken to a hospital with minor injuries, he said.

The crash remains under investigation.