Two teenagers were arrested Wednesday after they pulled a gun on a man who met up with them to sell a cellphone, Anchorage police said.

Officers responded to a 4:11 p.m. report of a robbery at the Tesoro gas station on Muldoon Road, where the victim told them he had been robbed at gunpoint, according to a police statement.

The man told police he arranged to sell his iPhone X through Letgo, a smartphone app for people looking to buy and sell goods.

He agreed to meet the buyer at Fourth Avenue and Patsy Drive. He arrived at the spot and remained in his vehicle, then saw two boys walk by his car a few times.

Then the boys approached him. One asked to see the man's phone, then stepped aside. The other teen pulled out a handgun, held it to the man's head and told him to drive away.

Before the man could drive off, the teenager fired once into the air, police said. The man drove away and called police. Nobody was hurt.

The first teenager had used his real name when arranging the meeting, and his name was recognized by a school resource officer, police said. When officers got to the boy's home on the 400 block of Oklahoma Street, they saw him peering from a window.

At 5:11 p.m., both teenagers came out of the house. They were arrested and taken to the McLaughlin Youth Center. The gun suspected of being used in the crime and the stolen iPhone were recovered, police said.

Police offered tips to the public on precautions to take when selling goods online:

– Go to the meeting spot with at least one other person.

– Meet in a visible public place where there are "cameras and a lot of foot traffic," and during a busy time of day to make sure other people are around.

– Write down the license plate of the vehicle the person arrived in, and note physical attributes.

– Accept only cash, not checks or cashier's checks, which can be forged. Make sure the money you're accepting looks and feels real, not counterfeit.