Dicarlo Bennett, a 28-year-old employee for the ground handling company Servisair, was booked Tuesday for possession of a destructive device near an aircraft. He is being held on $1 million bail.
Police had stepped up patrols and increased its checks on employees after the blasts took place Sunday night and then again Monday night.
Bennett took the dry ice from a plane and placed it in an employee restroom Sunday night and another device that was found on a tarmac outside the international terminal, according to a law enforcement official briefed on the investigation who wasn't authorized to speak publicly.
Police had previously said they didn't believe the explosions were an act of terror because of the locations of the devices and because people weren't targeted.
No one was injured in either incident, although some flights were delayed Sunday.
"The incidents could be the work of a disgruntled employee due to an internal labor dispute," said Los Angeles Police Department Deputy Chief Michael Downing, who heads the department's counter-terrorism and special operations bureau.
Swissport recently agreed to acquire Servisair and the transaction is expected to close by the end of the year. An afterhours message seeking comment from Servisair was not immediately returned.
It wasn't immediately known what Bennett's motives were, but he was riding in a van with several others, including a supervisor, when he decided to plant one of the dry ice bombs, the official told The Associated Press. Those in the van were aware of the dry ice, the official said, but no other arrests have been made.
The bombs were made by putting dry ice in 20-ounce plastic bottles and could have caused serious injury to anyone in close proximity, Downing said.
One device exploded in an employee men's room Sunday night in Terminal 2. Remnants of an exploded bottle also were found that night on the tarmac area near the Tom Bradley International Terminal, but an employee threw it away. The same employee found an unexploded bottle Monday evening and then reported what he found the previous day.
While there are cameras in some of these restricted-access areas, Downing said there isn't as much camera coverage as in the public-access areas and investigators had been reviewing available video.
Dry ice is widely used by vendors to keep food fresh.