A gunman who went into a Catholic supply store in suburban St. Louis, sexually assaulted at least one woman and shot a woman in the head is being sought by police Monday night.

Police are looking for a white man about 5-foot-7 with a heavy build and said he should be considered armed and dangerous, as The St. Louis Post-Dispatch reported.

The shooting happened about 3:15 p.m. at a Catholic Supply of St. Louis store in western St. Louis County, near the town of Ballwin.

The gunman walked into the store and sexually assaulted at least one woman — police spokesman Shaun McGuire said he couldn’t confirm media reports that more than one woman was assaulted. The shooting victim was in critical condition at a hospital, authorities said.

It wasn’t clear why the store was targeted, and McGuire didn’t know if its religious affiliation was a factor.

Catholic Supply of St. Louis Inc. operates three stores specializing in church supplies for parishes as well as Catholics. The company’s website said it also publishes national supply catalogs.

“Our hearts go out to the victims of this horrific tragedy at Catholic Supply,” St. Louis Archbishop Robert Carlson said in a statement. “We are praying for these victims, especially the victim in critical condition at this time.”

Authorities said the woman who was shot did not know the suspect.

“Obviously, that adds to the intensity of our search,” McGuire said.

The shooting happened at a strip mall in an affluent area of about 25 miles west of St. Louis along Manchester Road, one of the most congested roadways in the region.

McGuire said the heavy volume of traffic only made finding the suspect more difficult.

“Obviously someone could blend in pretty easily,” he said.

The Associated Press contributed to this report.