Los Angeles police are questioning three people Monday after two undercover police officers were targeted by gunmen Sunday night while driving through a southern city neighborhood, in what is believed to have been a calculated attack.

Detective Meghan Aguilar told the Los Angeles Times that the plainclothes officers were grazed by bullets in the Florence neighborhood around 5:45 p.m. local time, while driving in an unmarked police car, and returned fire. 

She said there was no indication that the officers were caught in crossfire between rival gangs. 

"There's going to be several thorough interviews of the officers. But right now they believe they were the target," Aguilar told the Los Angeles Times.

Both officers suffered minor injuries and were treated at the scene. Authorities apprehended several people at the scene and the search is ongoing for more suspects, Aguilar said.

A SWAT team and a K-9 unit, along with dozens of officers, were seen combing the neighborhood for shell casings and potential witnessses. 

Several blocks remained shut down Monday.

"We are asking the public to shelter in place and notify police if they see any unusual activity in their houses or yards," Aguilar said Sunday night.

Junior Moore, 54, said he was eating at a fast-food restaurant when the gunfire erupted about 5:45 p.m.

"I heard, like, 20 shots and then a bunch of police sirens," Moore told the Los Angeles Times.

The Associated Press contributed to this report. 

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