LOS ANGELES — The report of a school police officer shot last week touched off one of the largest Los Angeles-area manhunts in recent memory and forced thousands of students to remain in their classrooms for hours as officers searched for the attacker.

Now law enforcement officials allege Officer Jeffrey Stenroos was lying when he said a gunman shot him in the chest as he patrolled near a San Fernando Valley high school Jan. 19. He was arrested Thursday night on suspicion of filing a false police report.

"The current state of the investigation refutes Stenroos' initial account of the incident and we are now certain that there is no outstanding suspect in this shooting," Police Chief Charlie Beck said at a news conference Thursday night.

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A law enforcement official, who asked not to be named because he was not authorized to speak about the case, said Stenroos was mishandling a firearm when he was shot, but he did not go into any more detail.

Bulletproof vest
Beck did not say what the motive might have been, or what led police to believe that the incident was a hoax, Los Angeles station KNBC-TV reported. Stenroos was free on $20,000 bail as of Friday, the report said.

The gunshot hit Stenroos in his bulletproof vest and authorities said that protection saved his life. He was treated for minor injuries and released from the hospital later that night.

Beck defended the aggressive police response to the shooting, which occurred one day after a gun accidentally fired in a student's backpack at another Los Angeles high school, wounding two students.

"We go where these investigations take us," he said. "Finding the truth and obtaining some form of justice is what we're about."

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More than 350 officers from five agencies scoured the area, gathering hundreds of clues, canvassing neighborhoods and reaching out to residents to drum up leads in the case, Beck said.

The day of the shooting, nine schools with about 9,000 students were locked down as more than 350 police officers, sheriff's deputies and California Highway Patrol officers scoured 7 square miles of the affluent Woodland Hills neighborhood around El Camino Real High School for the gunman, described as man in his 40s with long brown hair.

Students were kept in their classrooms for hours without access to food or bathrooms, prompting anger and frustration from parents.

Authorities later mustered $100,000 in reward money for information leading to the suspected shooter's arrest.

"Obviously, it's as shocking to us as it is to anyone else," Los Angeles Unified School District Police Department Chief Steven Zipperman said, according to the Los Angeles Times. Zipperman, who recently departed the LAPD to take his current post, said the department is cooperating with the investigation, the newspaper said.

Los Angeles Police Protective League president Paul Weber said he was "disgusted" to hear about Stenroos' arrest and apologized to the public for his actions.

"His lies set into motion the largest search for a suspect in recent history and inconvenienced thousands of people for hours," the police union president said. "If these allegations are proven true, Mr. Stenroos is now where he belongs, behind bars."