UPDATE 2-Fugitive ex-Los Angeles cop in shootout with police

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LOS ANGELES, Feb 12 (Reuters) - Fugitive former policeman Christopher Dorner exchanged gunfire on Tuesday with San Bernardino County sheriff's deputies in the mountains northeast of Los Angeles after he broke into a home, tied up a couple and stole their pickup truck, authorities said.

Two officers involved in the shootout were struck by gunfire, a spokeswoman for the sheriff's department said. One wounded officer was flown by helicopter to an area hospital, a spokesman for the county fire department said.

Dorner, accused of targeting police officers and their families in three revenge-driven killings, was apparently fired upon by a state fish and game ranger as he fled in the stolen vehicle, the Riverside County Sheriff's department said.

Local television news outlets aired the sounds of gunfire and shouting in a live broadcast from the Big Bear Lake ski resort area.

The confrontation came on the sixth day of a search for Dorner that Los Angeles Police Department Chief Charlie Beck has called the most extensive manhunt in the region's history.

Dorner's last confirmed encounter with authorities came early last Thursday, when police said he ambushed two policemen at a traffic light in Riverside, about 60 miles (100 km) east of Los Angeles. One of those officers was killed, the other wounded.

That shooting came shortly after Dorner, a former Navy officer, is suspected of exchanging gunfire with police in nearby Corona, wounding one officer there.

Last Wednesday, he was named as a suspect in the slayings of a campus security officer and his fiancee, the daughter of a retired Los Angeles Police Department captain who Dorner blamed for his 2008 dismissal from the department in a manifesto posted on his Facebook page last week.

In the rambling online declaration, Dorner claimed he was wrongly terminated and vowed to seek revenge by unleashing "unconventional and asymmetrical warfare" on police officers and their families. (Reporting by Dan Whitcomb, Steve Gorman and Alex Dobuzinskis; Writing by Steve Gorman; Editing by Cynthia Johnston and Leslie Adler)