A San Diego Police Department officer has died and another officer remains hospitalized after a late-night shooting during a traffic stop just south of downtown San Diego. Both officers are part of the force's Elite Gang Unit.

The SDPD said one suspect is in custody and authorities continue to search for other possible suspects.

At around 8:10 a.m. Friday, officers surrounded a home in San Diego's Shelltown area -- at 41st and Epsilon streets -- honing in on another possible suspect.

SWAT officials could be heard calling out to someone inside the home, saying, "Come to the door. It's been a long night."

The sounds of dozens of flash bangs filled the air as the SWAT standoff unfolded.

At a press conference earlier Friday morning, SDPD Chief Shelley Zimmerman said the officers were conducting the traffic stop shortly before 11 p.m. Thursday in the city's Southcrest neighborhood when they were fired upon.

Shortly after stopping their car, the officers called for emergency cover.

Additional SDPD officers swarmed the area and found both officers suffering from gunshot wounds.

One officer, who suffered multiple wounds, was rushed in a patrol car to Scripps Mercy Hospital in Hillcrest. Doctors were unable to save his life. He was married and a father of two, Zimmerman said.

The second officer, the father of a 19-month-old baby, was taken to UC Medical Center, also in Hillcrest, where he underwent surgery. As of Friday morning, the officer was resting comfortably but had not woken up yet, Zimmerman said. His wife has not left his side.

The mood at the hospital was somber as dozens of officers from all ranks came in and out of the building all morning. Zimmerman said the situation was simply heartbreaking for her police department. She stayed at the hospital, comforting the families of the officers.

Other SDPD leaders, including Asst. Chief Terry McManus and Capt. David Nisleit, also visited the hospital. As officers filed in, they greeted one another with hugs and pained expressions.

Sources told NBC News that it appeared the suspects are believed to belong to a local San Diego gang and there was no indication at this stage of the investigation that the officers were specifically targeted as in recent incidents in Dallas and Baton Rouge that collectively claimed the lives of eight officers.

Still, they stressed that the investigation is still in its preliminary stage.

Following the shooting, police launched a manhunt for the suspects then took one suspect, who has not yet been identified, into custody. The suspect also suffered from a gunshot wound and was being treated at a hospital.

The search continued Friday morning for possible additional suspects as authorities used a helicopter, SWAT vehicles and patrol cars to scour the area.

NBC 7 San Diego viewer, Raul Meza, lives next to Interstate 5. In a comment posted to Facebook, Meza said he couldn't count the number of police cars he saw descending on Southcrest.

"I couldn't even tell you how many cop cars were racing down the freeway," Meza wrote on NBC San Diego's Facebook page. "I've never seen anything like that before."

SDPD officials are expected to hold another news briefing later Friday morning.

The last time an SDPD officer was killed in the line of duty was in 2011, when Officer Jeremy Henwood was shot in San Diego's City Heights community.

"We grieve for our fallen officer and stand with his family during this very difficult time," San Diego Mayor Kevin Faulconer said in a statement Friday morning. "We also pray for the second officer shot last night as he recovers from surgery. Violence against the men and women who wear the badge is violence against us all. I ask all San Diegans and all people across our nation to join together in support of our officers who courageously protect our communities. We need them and they need us."