The incident happened around 7 p.m. in a Terminal 2 employee restroom that is not accessible to passengers, according to LAX police.
Nobody was hurt when the dry ice exploded, but it did lead to a temporary shutdown of flight departures from Terminal 2. Security screening was also halted for about an hour. The terminal was not evacuated.
The FBI said Monday the LAPD will take over the investgation. No arrests have been made and there were no stated threats associated to the incident.
Passengers say airport personnel did let them know there was a security problem.
"First we noticed that the baggage conveyor belt stopped and they stopped all baggage going through. Apparently we heard that there was a security breach. Nobody had to evacuate or anything. No police came through, and basically everything was a standstill; basically waited until it cleared," said Illona Zigetvari, a passenger.
Investigators are examining the area for evidence to try to figure out who is responsible for the dry ice bomb.