By Amy La Porte, CNN
Updated 11:48 AM ET, Sat March 10, 2018

(CNN) A standoff between police and an armed suspect that resulted in one officer's death and the wounding of another remains underway Saturday morning in Pomona, California, near Los Angeles, more than 12 hours after it began.

The suspect is barricaded inside an apartment home after fatally shooting an officer and wounding a second one, according to the Los Angeles County Sheriff's Department.

"It is with a heavy heart that I must report that one officer did not survive," Pomona police Chief Michael Olivieri tweeted early Saturday morning. "The second officer is in stable condition."