RALEIGH, N.C. (AP) — Police say they’ve found no evidence of any gunfire and can’t explain what kind of loud noise led people to flee in fright from a busy North Carolina shopping mall.

Eight people were hospitalized after being trampled in the rush to escape from what were reported as gunshots inside Raleigh’s Crabtree Valley Mall on Saturday.

Raleigh police say they’ve interviewed all known witnesses to the incident and can’t find any indication that a gun was fired and can’t explain what caused the loud noise that people reported. No one suffered gunshot wounds and no shell casings were left behind by fired bullets.

Video posted on social media sites shows dozens of people running toward mall exit doors as numerous screams were heard.