Updated

A supervisor on the runways of Los Angeles International Airport has become the second airport employee arrested for setting off a dry ice bomb, officials said.

Miguel Angel Iniguez, a 41-year-old supervisor for the aviation ground services company Servisair, has admitted to placing one of the dry ice bombs outside the airport's Tom Bradely International Terminal while a plane was parked nearby, according to a law enforcement official briefed on the investigation but not authorized to speak publicly.

The suspect was arrested Friday night while at work and booked on suspicion of possessing a destructive device near an aircraft, LAPD Cmdr. Andy Smith said. He was being held on $500,000 bail.

Iniguez was the supervisor for the first man arrested, Dicarlo Bennett, 28, who was taken into custody Tuesday night for allegedly setting the devices, the official said. He pleaded not guilty Thursday to two counts of possessing a destructive device in a public place.

No one was hurt when a plastic bottle packed with dry ice exploded Sunday in an employee bathroom and another blew up on the airport's tarmac. An employee found a third plastic bottle expanding Monday night on the tarmac near where the other exploded.

Bennett was riding in a van with several people Sunday night when he decided to make the dry ice bombs in plastic bottles, the official said. Those in the van were aware of the dry ice, though no one else was initially arrested, and it wasn't clear if more arrests were planned.

Police said Dicarlo planted the three devices out of personal curiosity. They'd initial worked on the theory that dry ice bombs were the work of a disgruntled employee due to an internal labor dispute. Swissport recently agreed to acquire Servisair and the transaction is expected to close by the end of the year.

Servisair did not immediately respond to a request for comment, and police did not immediately know if Iniguez had retained an attorney.

Los Angeles police officials said building dry ice bombs is a felony.

A man was killed in 1992 while cleaning a liquor store in Los Angeles when a kid created a dry ice bomb with a glass bottle and the man picked it up. Glass shards slit his throat and he bled to death.