CARLSBAD, Calif. -- An Encinitas gang member was behind bars Monday on suspicion of killing a 21-year-old man in Carlsbad over the weekend, police said. Two other men were taken into custody Monday, afternoon, police officials said.

Javier Lopez, 19, was arrested Sunday in connection with a fatal shooting that occurred in the area of Pine Park on Saturday, Carlsbad police Lt. Neil Gallucci said.

Lopez is accused of killing Juan Carlos Balderas of Encinitas whose body was discovered in a vacant lot at Chestnut Avenue and Madison Street, just west of Pine Park, around 8:30 p.m. Saturday, according to Lt. Kelly Cain.

A possible motive for the killing was not immediately released. An investigation by Carlsbad police gang detectives was under way, Gallucci said.

Lopez was being held without bail at the Vista jail. He could be arraigned as early as Tuesday afternoon at the Vista courthouse, according to the San Diego County Sheriff's Department's Web site.

Cain said Jose Barraza, 26, and Victor Lopez, 20, were arrested in connection with the case on Monday.