LOS ANGELES (AP) -- Police said Tuesday they don't believe two dry ice explosions this week in restricted areas at Los Angeles International Airport were an act of terror, and they're pursuing the theory that the blasts were the work of a disgruntled employee.
The bombs were made by putting dry ice in 20-ounce plastic bottles and could have caused serious injury to anyone in close proximity, though no one was hurt, said Los Angeles Police Department Deputy Chief Michael Downing, who heads the department's counter-terrorism and special operations bureau. Police are treating them as seriously as if they were pipe bombs.
"Our intent is to find the person who did it, build a prosecutable case, and put them in jail," he said.
Investigators have not identified a suspect. They were interviewing employees Tuesday and requesting that anyone with information come forward.
Police believe the explosions were set off because of an internal labor dispute and not terrorism because of the locations of the devices and because people weren't targeted, 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.
There were no reports of any injuries or evacuations. Flights were delayed Sunday night, but no flights were affected Monday.
While the two terminals are not connected, Downing said an employee could walk or drive between them on the tarmac.
Investigators were checking surveillance video and planned to hand out pamphlets to employees telling them about the serious nature of the crime and that it wouldn't be tolerated, Downing said.
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.
Investigators also were waiting for the results of fingerprints and DNA testing on the exploded devices, said Cmdr. Blake Chow, assistant commander of the counter-terrorism and special operations bureau.
Chow said while police are pursuing the disgruntled employee theory, they won't know for sure what the motive is until an arrest is made.
Airport police have increased patrols. The airport also has increased its checks on some employees — asking them to produce valid IDs — and will continue to do so until the case is solved, said Arif Alikhan, deputy executive director for Homeland Security and Law Enforcement at Los Angeles World Airports.
"We're increasing our presence, increasing our tempo, educating our employees, talking to all employers about this," Alikhan said. "We're doing everything we can."
Employees have to undergo a criminal history check and pass a security threat assessment to receive access badges at the airport, Alikhan said. To enter a restricted area, employees must swipe their badges, be on an access list or have ID verified by a security officer, depending on the location.
Depending on the type of work they do or their level of access, some employees might have to go through the TSA security checkpoint for screening to get to work, Alikhan said.
Dry ice is widely used by vendors to keep food fresh.
According to the Transportation Security Administration's website, passengers can pack perishables in up to 5 pounds of dry ice in their carry-on or checked baggage as long as it's properly packaged — meaning the package is vented. Even so, the agency reserves the right to not allow it on the plane if they believe it poses a security concern.
Tami Abdollah can be reached at https://www.twitter.com/latams