BETHESDA, Md. (AP) — A woman was killed and three people were wounded in two shootings within an hour Friday at a mall and a shopping center in the Washington suburbs, police said.

Officers responding to a report of a shooting in the parking lot of Westfield Montgomery Mall in Bethesda on Friday morning found three people shot, Montgomery County Police Assistant Chief Darryl McSwain said. One person was shot and two others may have been shot coming to that person's aid, he said. There's no reason to believe the victims knew the shooter, he said.

About a half an hour later, police were called to a shooting at a Giant Food store in Aspen Hill, about 5 miles away. Police later tweeted that a woman died after that shooting. It's not clear if the shootings are connected.

No one is in custody, McSwain said, but police are looking at a person of interest.

The upscale mall is located in Bethesda, about 10 miles northwest of downtown Washington.

Police in neighboring Prince George's County are looking into the possibility that the shootings could be connect to a fatal shooting at a high school on Wednesday, spokeswoman Julie Parker said. The suspect in that shooting was still on the loose.

All schools in Montgomery County are sheltering in place at the request of police, county schools officials said in a statement. Schools were given a "shelter-in-place" order around 1 p.m., schools spokeswoman Gboyinde Onijala said. That means classroom activities will continue but all students staff and visitors are being brought inside and doors are locked.