Miguel Angel Iniguez, 41, a ground services supervisor with Servisair, was arrested Friday on suspicion of possession of a destructive device, the Los Angeles Times reported.
Authorities said Iniguez was the supervisor of Dicarlo Bennett, who was arrested earlier this week for allegedly planting the devices.
Bennett allegedly placed the dry-ice bombs in employee-only areas in the airport on Sunday. One went off later that day and one went off Monday, while a third did not detonate.
The bombs delayed flights and prompted investigations by a bomb squad at the airport two days in a row, authorities said.
Police said Bennett allegedly planted the bombs for his own amusement.
"He was a prankster," Deputy Chief Michael Downing said. "He thought it was funny."
Los Angeles Police Chief Charlie Beck said the bombs were "more of a noise device than a device that causes damage."
However, "whether you think this is a harmless prank or a way to disrupt operations at the airport, it won't matter," Beck said. "You will go to jail."