The manhunt continues for America's most wanted man

The Los Angeles Police Department has been stretched to the limit after five days hunting for Christopher Dorner.

An exhaustive search involving dogs, snowmobiles and helicopters was scaled down on Monday as no trace was found of the 33-year-old former police officer who has declared "war" on his own force and is suspected in three killings.

Dorner was last spotted in Big Bear, 80 miles from Los Angeles, on Thursday. Around 50 LAPD officers and their families remain under protection at their homes amid fears Dorner would target them.

A $1 million bounty has been put up by the city.

One of the three victims was Monica Quan, 28, whose father Randal Quan, a retired police captain, represented Dorner at a tribunal when he was sacked from the the LAPD five years ago.

Captain Quan subsequently received a taunting phone call about the death of his daughter, and police are investigating whether it was Dorner who made it.