CONCORD -- Three suspects have been arrested and charged in connection with a March 16 double homicide in Concord and authorities are looking for a fourth suspect, who has been charged, but not yet located, Concord police Lt. Andrew Gartner said Tuesday.

Terrance Brewer, a 19-year-old Pittsburg resident, was arrested in New Orleans, Correy Roseboro, a 20-year-old Antioch resident, was arrested in Texas and Dominic Disibio, a 20-year-old Brentwood resident, was arrested in Concord, Gartner said.

Brewer was booked into the Martinez Detention Facility April 16, Roseboro was booked April 11 and Disibio was booked March 22, a county jail official said.

They are each facing charges of murder, robbery and assault with a firearm on a person, officials said.

Brewer's bail has been set at $2.25 million, Roseboro's at $1.25 million and Disibio's at $1 million, officials said.

The charges stem from a March 16 incident that appears to have begun in a Safeway supermarket parking lot at 4309 Clayton Road at Denkinger Road, police reported.

Police, however, were first called to the 4000 block of Sacramento Street shortly before 8:30 p.m. that night and found Adam Bella, a 20-year-old Pittsburg resident, and Abdiel Mejia, a 21-year-old Concord resident, shot to death inside a car that had stopped in the middle of the street.

A third man, Abdiel Mejia's brother, Aaron Mejia, 22, was found in a driveway suffering from gunshot wounds but still alive, police said.

From the position of the bodies inside the car, an older model green Cadillac, it appeared that the two dead men had been struggling over a gun in the front seat, Gartner said.

Investigators said Aaron Mejia appeared to have been driving the Cadillac. He was taken to John Muir Medical Center where he underwent surgery.

As police were collecting evidence at the Sacramento Street crime scene, they received a call from the nearby Safeway store on Clayton Road, Gartner said.

Officers responded to that location and found four spent shell casings in the parking lot and evidence suggesting that the Cadillac had crashed into a parked car as it fled the area.

A witness told police they had heard an argument in the parking lot and then at least four shots fired.

Police recovered one gun from inside the Cadillac, along with some marijuana and a small amount of cash that were allegedly in plain view, leading investigators to suspect that the killings were the result of a drug deal gone bad, Gartner said.

Police said in the days following the killings that they believed Bella and Brewer had met the Mejia brothers in the parking lot for a pre-arranged drug deal.

It was not immediately clear where Roseboro, Disibio and the unnamed suspect were during the incident.

The two groups apparently had a disagreement and shots were fired from both outside and inside the vehicle with two different caliber guns, Gartner said.

Disibio is scheduled to enter a plea to the charges on Wednesday, Brewer on Monday and Roseboro on May 12 in Contra Costa County court in Martinez.

Aaron Mejia so far has not been charged, according to the district attorney's office.