NATIONAL CITY, Calif. - Police Monday arrested a suspect in a shooting that fatally wounded a man in an East County residential neighborhood last week.

Antonio Garcia, 32, was taken into custody about 3:30 p.m. at a relative's home on G Avenue in National City.

Garcia allegedly shot 33-year-old Josue Rodriguez, address unknown, in the back of the head in the 5800 block of Amarillo Avenue in La Mesa shortly before 5:30 p.m. Thursday, Capt. Dan Willis said. Rodriguez was pronounced dead at a hospital.

The motive for the slaying remains unknown, though witnesses reported hearing an argument between two men just before the gunfire rang out, according to Willis.

It also was unclear why the victim was in the neighborhood where he was slain. He had driven there but was on foot when he was shot, possibly while trying to run away from the assailant, Willis said.

The gunman apparently left the scene on foot and was picked up by someone in a vehicle a short time later.

The captain declined to disclose what led detectives to identify Garcia, a La Mesa resident, as the alleged killer.

Garcia was expected to be booked into county jail on suspicion of murder.