Four teenage boys were arrested for investigation of a series of attacks on homeless people that were recorded on their cell phone cameras, police said Monday.

The three 17-year-olds and one 15-year-old shot plastic pellets from a pistol, threw smoke bombs and even a bicycle at the men in several incidents this month, said police Lt. Paul Vernon. He said the teens planned to post the videos online.

"Their intent was to make the videos public domain on the Internet," Vernon said. "Luckily they were caught in the act and we foiled their effort."

Three of the teens were arrested on Skid Row early Sunday after patrol officers saw them recording a homeless man whose blanket caught fire from a smoke bomb, Vernon said.

The victim was not seriously injured.

Names of the teens were withheld because they are juveniles.

Investigators seized each of their cell phones and found video of other attacks, including footage of a homeless man under a blanket shot with an airsoft pistol and a bicycle thrown into another homeless man's tent, police said.

The cell phones recorded four incidents early Sunday showing smoke bombs thrown at homeless men or a group of men sleeping on Skid Row and in an industrial area south of downtown. Two other incidents occurred around July 3 and 4.

None of the victims' faces were shown in the recordings, Vernon said. He said the videos will not be released because "that's just what the boys want to achieve."

Vernon said the teens told investigators they have watched and were influenced by "Bumfights," a video series that feature homeless people battering one another for money.

The fourth teen was arrested Monday and a pellet gun was seized from his house, the lieutenant said.

Vernon declined to comment on whether the teens could be seen or heard in any of the recordings, saying only that detectives have evidence connecting them to the attacks.

The teens were being held without bail at a county juvenile hall. They could be charged with assault with a deadly weapon and arson, and would be tried in juvenile court, Vernon said.