Six people were injured after a gunman opened fire at a mall in Houston, Texas Monday before police shot him, police and firefighters said.

Houston Fire Department spokesman Richard Mann said the injuries were of varying gravity with some suffering gunshot wounds and others cut by broken glass.

"Several people shot by suspect are being transported to area hospitals; unknown exact number or severity of injuries," the Houston police said on its Twitter account.

Police shot the "active shooter" and there were "no reports of other suspects at this time," it said.

Mann said the shooter had not been taken to the hospital, because experts were checking his vehicle for explosives.