PHOENIX - Two people were hospitalized Thursday morning after a four-vehicle collision involving a school bus in Glendale, authorities said.

There were no children in the bus when the crash occurred near Olive and 59th avenues, the Glendale Police Department said.

The driver and a passenger of a truck were taken to a hospital with serious injuries, according to preliminary information provided by police.

The investigation is ongoing. No other details were immediately available.