TULALIP — Detectives are investigating a shooting at a Walmart parking lot on the Tulalip Indian Reservation on Tuesday that sent one man to the hospital on his 29th birthday.

The man was treated for a gunshot wound to the shoulder at Providence Regional Medical Center Everett on Tuesday night before being booked into the Snohomish County Jail for investigation of robbery and a parole violation Wednesday morning.

His accomplice, 21, was booked into the Snohomish County Jail for investigation of robbery and theft.

The men are accused of stealing two ounces of marijuana from a Tulalip man at gunpoint.

That man, 23, said the men hit him in the face with a handgun and shot out his front passenger-side window. He fired back with his own gun, and said his actions were self-defense, according to court records.

Detectives had the car impounded.

“They are still gathering evidence,” Snohomish County Sheriff’s Office spokeswoman Shari Ireton said Wednesday.

The Tulalip man told detectives that he sells medical marijuana and had taken out an ad on Craigs-list. He agreed to meet with the men Wednesday night.

After the shooting, the Tulalip man drove home to tell his wife what happened. They then went to the Washington State Patrol headquarters west of Marysville to report the shooting. The case was turned over to Tulalip Tribal Police who asked for assistance from the sheriff’s office Major Crimes Unit.

At the hospital, the injured suspect told detectives he was shot at a party in Everett. When asked if he had been in the Tulalip supermarket parking lot earlier that evening, he allegedly became uncooperative.

An acquaintance of both suspects said he drove the men from the Tulalip supermarket parking lot to Everett and dropped them off at the emergency room, according to court records.

Eric Stevick: 425-339-3446; stevick@heraldnet.com.