Houston police are investigating an overnight robbery spree that saw four robberies in 30 minutes.

The spree started at a Chevron and McDonald's combination on the North Freeway and Lockwood Drive.  Witnesses say three to five men first robbed the Chevron then the McDonald's before firing their guns in the parking lot as they sped away.

Then less than 30-minutes later a Valero station and a convenience store were robbed simultaneously.  Police suspect the same men are responsible for all the robberies.

Right now police are reviewing surveillance video but say the men were wearing mask so they don't have any descriptions.