Three Lexington public school students sustained “bumps and bruises”’ when their bus was involved in a chain-reaction crash shortly after 8 a.m. Friday, Lexington police said. The bus was en route to the Bridge Elementary School at the time of the crash, police said. School officials said Bus 28 was the only one involved in the accident. The three students were taken to local hospitals for evaluation, police said. According to police, two cars collided with one another, and the bus, in turn, struck the two vehicles around 8:15 a.m.John R. Ellement can be reached at email@example.com.