Two men were killed, and two others were wounded in a shooting in National City Saturday that prompted an eight-hour standoff.
Alejandro Robles, 24, was arrested on one count of murder and was booked into jail Sunday. The names of the other three men have not been released yet. Officials say they are not looking at any other suspects.
By 5:30 p.m., authorities were able to take one suspect into custody who had been holed up in an upstairs apartment in the 1000 block of E. 8th Street. For hours, officers with the National City Police Department (NCPD) and SWAT officials had been trying to negotiate his surrender.
Finally, he walked down the stairs, unarmed, and gave himself up to authorities. He was suffering from unspecified wounds and was taken to a hospital, escorted by police.
Inside the apartment, NCPD Capt. Jose Tellez said investigators found a second man. He had suffered apparent gunshot wounds and was dead.
The ordeal in the neighborhood began around 9:25 a.m. when a 911 caller reported the sounds of shots being fired near a four-unit apartment building on E. 8th Street. Moments later, police received a call from a man saying he had allegedly shot someone in the head.
Police, firefighters, medics, and SWAT officials rushed to the scene.
Tellez said that when officers arrived, they found two men wounded outside the residence. One man was dead on the sidewalk; the other was suffering from severe injuries, including a gunshot wound to his upper body. That man was taken to a hospital.
A large part of the street was cordoned with yellow tape as officials assessed the situation and searched for suspects. About 20 minutes later, more ambulances were requested at the location.
Shortly after that, SWAT officials were in position, zeroed in on an apartment where a man linked to the shooting was barricaded. NCPD investigators said the suspect was believed to be armed.
Authorities deployed a robot into the apartment as well as a drone to gather more information about what was happening inside.
Tellez said the robot detected two men inside the apartment; one man was hurt but moving around while the other was dead from apparent gunshot wounds.
Using megaphones and cell phones, SWAT negotiators began communicating with the man who was walking around the apartment. Officers could be heard calling out the man's name, but he refused to come out.
A standoff ensued.
Police advised motorists to avoid the area between the 600 and 1200 blocks of E. 8th Street. The neighborhood is also home to several eateries and strip malls filled with shops.
Police told residents to shelter-in-place, from E. 8th Street and Highland Avenue to E. 8th and M streets, until the standoff was over.
As dozens of law enforcement vehicles descended on the neighborhood, a police helicopter monitored the situation from above.
Just after 12 p.m., another man not linked to the shooting or standoff was detained by police in front of the home after he confronted officers. The man was heard yelling, "That's my son in there!" referring to one of the men inside the apartment.
The standoff pressed on, with access to the neighborhood completely shut down for several more hours.
Finally, Tellez said negotiators were able to get the man to come out of the apartment. It is unclear, at this point, if that man is the shooting suspect.
Tellez said officers who searched the apartment found multiple firearms inside, as well as narcotics. The homicide investigation is ongoing. The motive for the shootings is unknown.
Police have not yet released the names of the victims who were killed or of the two wounded men who survived -- including the suspect arrested in the standoff.
All four men are in between 20 and 35 years old, Tellez said. Investigators are still trying to determine who is a victim and who is a suspect in this case.
Some street closures remained in effect Saturday night while officials continued their investigation.