Authorities in Los Angeles have offered a $1 million reward for information leading to the arrest of a fugitive ex-policeman suspected of three murders, BBC News reported.

Christopher Dorner, 33, has been on the run for the past week, following the attacks in southern California.

Announcing the reward, Los Angeles Mayor Antonio Villaraigosa said his "reign of terror" must end.

In an online manifesto, he swore to take revenge on police officers he blamed for his firing in 2008. "We will not tolerate anyone undermining the security, the tranquility of our neighborhoods," Mr Villaraigosa said at a news conference announcing the reward on Sunday, Feb 10.

"We will not tolerate this reign of terror that has robbed us of the peace of mind that residents of southern California deserve," he added.

Dorner, a former officer of the Los Angeles Police Department (LAPD), is suspected of killing three people, including the daughter of a retired captain who represented him in a disciplinary procedure.

Police are now protecting 50 families, many belonging to former LAPD colleagues, against whom Dorner has vowed revenge for ruining his career.

In his online manifesto, Dorner suggested that some were motivated by racism.

Police are combing an area near Big Bear Lake, 80 miles (130 km) east of Los Angeles, after finding the suspect's burned-out truck near a ski area.

Dorner is suspected of: Shooting dead Monica Quan, 28 - the daughter of a former LAPD captain - and her fiance Keith Lawrence, 27, on Sunday night in their car at their home in Irvine, California;Shooting at two police officers, grazing one, on Thursday morning in Corona, east of Los Angeles;Ambushing two policemen in their patrol car in the town of Riverside a few hours later, killing one and wounding the other.

A former U.S. Navy reservist, Dorner lost his job for making false statements.

According to court documents, He was fired in 2008 after making a complaint against his field training officer, saying she had kicked a suspect, a schizophrenic man with severe dementia, during an arrest.