An Arizona brain scientist was arrested last week after two women said he pointed a semiautomatic rifle at them at an airport coffee shop.

Dr. Peter Nathan Steinmetz, a neuroscientist at Barrow Neurological Institute in Phoenix, brought the AR-15 rifle slung over his shoulder to Starbucks inside a terminal at Phoenix Sky Harbor International Airport.

The Phoenix New Times reported that Steinmetz was doing nothing wrong until he removed the weapon from his shoulder, accidentally pointing the gun at two women waiting at a gate.

Police told the newspaper that it’s not generally illegal to carry a semi-automatic rifle into the airport terminal, but Steinmetz was arrested because of “the way he was carrying it.”

The physician had bought a cup of coffee and then stopped in front of some gates in the non-secure area of Terminal Four, where he accidentally pointed the muzzle at a woman and her 17-year-old daughter.

The women told police they feared for their safety.

Steinmetz was arrested about 10:30 a.m. on two felony counts of disorderly conduct with a weapon.

He told officers that he had no other business at the airport besides buying a cup of coffee.

Steinmetz and his son brought firearms to the airport in November, two days after a fatal shooting at Los Angeles International Airport, to pick up the neuroscientist’s wife.

The doctor told police at that time he was exercising his right to bear arms, and no charges were filed in the incident.

It wasn’t immediately clear why Steinmetz brought the Ar-15 to buy a cup of coffee, but pro-gun activists have staged open-carry demonstrations at retail and restaurant chains across the country.

Blogger David Waldman, who tracks gun violence for Daily Kos, argues that open-carry activists intend the demonstrations to suggest the companies support bringing weapons into their stores.

“To the manager (and other witnesses) on site, the main focus of the event appears to be the guns themselves,” Waldman wrote. “For everyone else viewing the event only through photos distributed online, the main focus of the event is the brand. ‘Look who’s letting us do this! Look who’s on our side! Soon you’ll see us in your location!'”

Watch this video report posted online by KPHO-TV:

CBS 5 – KPHO