Seeking leads in a massive manhunt, Los Angeles authorities on Sunday offered a $1 million reward for information leading to the arrest of Christopher Dorner, the former police officer suspected in three killings.

Mayor Antonio Villaraigosa announced the reward, raised through several private and public donors, at a news conference at LAPD headquarters.

“Our dedication to catch this killer remains steadfast,” Villaraigosa said. “We will not tolerate this reign of terror.”

Meanwhile, authorities said camping gear was found along with weapons inside Dorner’s burned-out pickup truck. The vehicle found Thursday in the ski resort town of Big Bear Lake was so charred that investigators couldn’t be more specific about the nature of its contents, Sgt. Rudy Lopez said.

Also Sunday, police investigated a taunting phone call that may have been made by Dorner to the father of the woman they believe he killed last week. Two law enforcement officers who requested anonymity because of the ongoing investigation told The Associated Press they are trying to determine if the call days after the killing was made by the 33-year-old fugitive or a man posing as him.

SWAT teams with air support and bloodhounds fanned out for the fourth day to search for Dorner, who has vowed revenge against several former LAPD colleagues whom he blames for ending his career.

The effort was significantly scaled back as the weekend went on, with 25 officers and a single helicopter looking for clues in the forest and going door-to-door at some 600 cabins in the San Bernardino mountains, about 80 miles northeast of downtown Los Angeles.

On Saturday, Chief Charlie Beck said officials would re-examine the allegations by Dorner that his law enforcement career was undone by racist colleagues. While he promised to hear out Dorner if he surrenders, Beck stressed that he was ordering a review of his 2007 case because he takes the allegation of racism in his department seriously.

“I do this not to appease a murderer. I do it to reassure the public that their police department is transparent and fair in all the things we do,” the chief said in a statement.