LENEXA, Kan. (AP) — Investigators have determined that the windshield on a Lenexa patrol cracked from a stress fracture and not from a bullet as earlier believed.

The Kansas City Star reports a stress fracture in the glass caused the rear window to shatter on the parked police car Thursday.

Authorities shut both a section of Kansas 7 for about three hours while police searched for a possible shooter after the officer reported the broken windshield.

Police said investigators determined that the stress fracture caused the window to “buckle and make a loud noise.”

They reopened the road shortly later Thursday afternoon.

During the search for a shooter, three schools in the area were placed on lock down.