San Diego SWAT officers head out Friday after entering a house with a possible suspect inside. One San Diego officer was killed and another was wounded in a shootout. One suspect was taken into custody and another man who may have been involved was detained.

SAN DIEGO — Two San Diego police officers were shot — one fatally — after a late-night stop turned into a gunfight, triggering a manhunt that led to the capture of one wounded suspect in a ravine and an hours-long SWAT standoff Friday that ended after officers detained a second man who may have been involved.

The shooting came as departments around the country are on high alert following the killing of officers in Dallas and Baton Rouge, Louisiana, this month. San Diego Police Chief Shelley Zimmerman said it was unknown whether the San Diego attack was premeditated.

The chain of events unfolded over more than 12 hours in a blue-collar area of southeastern San Diego with modest single-story homes. It started about 11 p.m. Thursday when two veteran gang unit officers in bulletproof vests stopped a person on a street. Almost immediately a shootout ensued and the officers called for backup.

Authorities initially said the officers made a traffic stop involving a motorist, but clarified later that they were still trying to determine whether it was a traffic stop or a stop to check out a pedestrian.

“It happened extremely quickly,” Police Chief Shelley Zimmerman said. “From the information that was put out that a stop was being made to that the officers called for emergency cover to when the other officers arrived on scene, we’re talking very, very quickly. Seconds to a minute or so.”

Jonathan DeGuzman, a 16-year veteran of the force who was married with two children, suffered multiple gunshot wounds. The 43-year-old died at a hospital after doctors’ efforts to save him failed.

Wade Irwin, 32, underwent surgery after being shot and was expected to survive, Zimmerman said.

Police swarmed the neighborhood where the shootout happened and quickly captured 52-year-old Jesse Gomez in a nearby ravine, Zimmerman said. He was in critical condition Friday with a gunshot wound but was expected to survive. Police gave no further information about Gomez or his role in the shootout except to say he was a suspect.

Zimmerman said late Friday afternoon that officers arrested another man in the area on an unrelated warrant and were investigating to see if he had any role in the police shootings.

After visiting Irwin at UC San Diego Medical Center early Friday, Zimmerman told reporters that the officer’s prospects for recovery were good. The nine-year veteran of the force had just joined the gang unit in June.

San Diego Mayor Kevin Faulconer denounced the shootings.

“I ask all San Diegans and all people across our nation to join together in support of our officers,” he said.