Two people, including an 8-year-old girl, were killed in a crash involving a semi-truck in Phoenix Friday.

Phoenix police say 25-year-old Roberto Manriquez Jr. and 8-year-old Alexandria Mendez were killed when a semi-truck crashed into the driver's side door of the pickup truck they were in.

The semi-truck, police say, was hauling an empty vehicle transport trailer and traveling westbound on Buckeye Road in the area of 69th Avenue before it turned into the eastbound lanes of Buckeye Road.

The semi-truck hit Manriquez's pickup and the truck's trailer hit another pickup truck. Manriquez and Mendez were pronounced dead at the scene.

Police say two other passengers in Manriquez's pickup truck, a 3-year-old boy and 28-year-old woman, were taken to a hospital with serious injuries. Both of them are expected to survive, police say.

The driver of the semi-truck and other pickup truck were not injured, police say.

According to police, the 50-year-old driver of the semi-truck said a mechanical failure caused his vehicle to turn into oncoming traffic.

Police say impairment is not believed to be a factor in the crash, but an investigation is ongoing.