Airline passengers may think twice about checking their bags after seeing a video released this month by Italian police.

The video is part of a hidden-camera sting that caught dozens of airline baggage handlers stealing from customers' checked luggage. Some brazen handlers even appeared to trash bags that had no valuables in them, according to authorities.

Police say they were able to catch the thieves after installing hidden cameras in the cargo holds of planes belonging to Italian carrier Alitalia. Among the thieves' loot, according to police, were cameras, cellphones, cash and other belongings pilfered from fliers' bags.

The Associated Press reports 29 handlers were arrested. UPI, the London Telegraph and London Daily Mail say another 57 were taken in for questioning. CNN adds all of those arrested were employees of Alitalia.

Alitalia says it cooperated with police, who conducted the hidden-camera sting at Rome's Leonardo da Vinci airport and about a half-dozen other Italian airports.

The investigation first began in 2011 at the airport serving the southern city Lamezia Terme, located in the "toe" of boot-shaped Italy, according to AP.

Lamezia Terme airport deputy police chief Ferruccio Martucci says investigators there were stumped about how the belongings were being stolen. He says they theorized the only place where handlers could be assured of secrecy was in the cargo holds. So, Martucci says police acted on that theory by installing temperature- and pressure-resistant cameras to the cargo areas of some Alitalia planes. That apparently allowed authorities to identify the handlers that they believed were responsible for the thefts. The investigation then spread to other airports.

If convicted, the accused handlers could be jailed for up to six years.

CNN adds that "the accused have been charged with criminal offenses including theft, aggravated theft and damage, since the luggage that they were not able to open was sometimes damaged out of spite, police said."