(LOS ANGELES) -- The effort is intensifying to locate Christopher Dorner, a highly-trained former Los Angeles police officer who is believed to be on a rampage to kill his former colleagues.
Police officers say Dorner has now become their worst nightmare -- a heavily armed man with the same training they have, plus a military background.
As the search continues, law enforcement officials are wondering whether Dorner has been engaged in diversionary tactics -- leaving a trail of false bread crumbs.
"He's extremely dangerous," said San Bernardino Sheriff John McMahon at a news conference on Friday. McMahon said that his officers, along with law enforcement and the FBI had been searching for Dorner all night, even with SWAT teams in snowcats on California's Bear Mountain.
Police are trying to figure out if Dorner deliberately dropped his wallet and his LAPD badge in San Diego, where earlier in the week he allegedly attempted to steal a boat to flee to Mexico.
"He knows what he's doing," L.A. Police Chief Charlie Beck told reporters. "We trained him. He was also a member of the armed forces. It is extremely worrisome and scary, especially for the police officers involved."
In a "manifesto" attributed to Dorner posted on the Internet, the former cop boasts about his combat skills, writing that he will utilize every bit of small arms training, demolition, ordnance and survival training he had been given in the LAPD, and in his career in the Navy.
Dorner is believed to be heavily armed, possessing an assault rifle and other weapons. Dorner also claims to have a .50 caliber rifle, which fires bullets five inches long -- capable of piercing bullet-proof vests, cutting through cars and some armored vehicles. Sources say it is likely that Dorner has such a rifle. The combination is concerning since Dorner's LAPD trainers rated him an "expert" sharpshooter with a .9 millimeter handgun, and "marksman" with an M-16 rifle.
Dorner has already cut a wide path of destruction. Chief Charlie Beck said at a news conference Thursday that Dorner "ambushed" two Riverside, Calif., officers as they sat in their squad car at a traffic light in the early morning hours. One officer, a 35-year-old, 11-year veteran of the force, was killed. His 27-year-old partner was seriously wounded.
Dorner is also wanted in the killings of Monica Quan and her fiance, Keith Lawrence, who were found shot to death in their car Sunday night, according to Irvine, Calif., police chief David L. Maggard. Quan is the daughter of a retired LAPD official, and Dorner allegedly threatened him and his family, among others, in his manifesto, according to police.
Now the manhunt for Dorner is in overdrive, and one source tells ABC News that just about anyone with a badge in southern California is looking for him. Local law enforcement agencies have activated "Code Alex," which triggers local police agencies to take up pre-planned observation posts as part of a mutual aid plan.
U.S. Marshals have obtained a federal warrant for Dorner's arrest and Thursday the FBI executed a search warrant in Las Vegas at a property Dorner is believed to have owned in the past.
Some officials hope that there will be a breakthrough soon, given the surge in media coverage. Dorner’s face is everywhere; his friends and associates are being run down. His resources are thought to be dwindling. He lost his car, he lost his wallet, and he can't use credit cards. As one law enforcement official put it, "His world is getting smaller every minute."
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