GRESHAM, Ore. – Police arrested four people on murder charges after a man was found shot dead in a car near a Gresham school Monday night.

The shooting occurred during a drug deal that turned into a robbery, court documents said.

Gresham police on Tuesday announced that 21-year-old Andrew McMahon of Gresham, 20-year-old Austin Brown of Portland, 17-year-old Tyler Mead of Gresham, and 17-year-old Amber Wilson of Gresham all face charges of first-degree murder and first-degree robbery.

Mead and Wilson are being tried as adults, which is why KGW is naming them.

Amber Wilson (left) and Tyler Mead.

Police identified the victim as 24-year-old Alexander Brodigan of Gresham. An autopsy confirmed Brodigan died of a gunshot wound to the head.

The investigation began when officers responded to a report of a gunshot near North Gresham Elementary School at 11:20 p.m. Monday. They found Brodigan dead inside a vehicle in the school's parking lot.

The car had hit the side of the school building. Witnesses said Brodigan crashed into the building after he was shot.

According to court documents, Brown told investigators that McMahon spoke with him earlier on Monday and said he needed help "hitting a lick," which Brown understood as stealing from a drug dealer.

Brown said he met Mead and McMahon at Mead's house near the school, and the group walked to the basketball court to meet their target, Brodigan. McMahon was armed with a semi-automatic handgun, but gave the gun to Brown after he became nervous, Brown told detectives.

Brown and McMahon approached Brodigan after he pulled into the parking lot and parked near a dumpster. McMahon and Brodigan got into a physical struggle over a large bag of marijuana that was on Brodigan's lap, court documents said. That's when Brown told police he pulled out the gun and pointed it at Brodigan because "he wasn't giving it up."

Brown fired a single shot at Brodigan and ran back to Mead's house with McMahon and Mead, he told detectives.

A witness told investigators he saw Brodigans's vehicle go in reverse and then a man fired a shot. The witness said he saw the vehicle crash into the building as three males ran from the scene.

Wilson told police that she took the handgun used in the shooting from her mother's house and brought it to Mead's house, according to court documents. She said she went with Mead, McMahon and Brown, and she was near the school when the shooting occurred.

Police used a K-9 to track the group to Mead's house. Investigators found the handgun hidden in a crawl space and the stolen marijuana in Mead's garage.

Vigil for Brodigan on Wednesday night

A community vigil for Brodigan was held at North Gresham Elementary School Wednesday night. Friends remembered him as loving person.

"Alex was a courageous guy and loyal and he loved every minute he got to spend with his daughter," said Maria King. "He was always smiling, goofy, but just a nerd. He was a good kid."