DENVER (KDVR) — Travelers leaving their vehicle at any of Denver International Airport’s parking lots will notice additional patrols as a sharp increase in thefts has led to beefed-up police presence.

“We have added additional patrols which will continue through the holidays,” said DIA spokesperson Alex Renteria.

An average of 50 cars have been stolen, per month, during the first three quarters of this year at and near the airport.

Thefts have increased as well.

Christopher Bart of Evergreen flew into Denver on Tuesday afternoon and discovered his catalytic converter had been stolen from his car parked in the Economy Lot. He wasn’t sure what he’d do next.

“I thought I’d ask at the ticket booth. Frankly, I will bet you what they are going to do is give me a legal answer that they are not responsible, and that I am and then I’ll leave. And I will think evil thoughts about the airport and their lax security,” said Bart.

Bart paid $17 a day to park his car. Replacing his catalytic converter will cost hundreds.

The Denver Police Airport Division said it’s also patrolling Rental Car Row. The division said it’s investigating auto thefts to hold suspects accountable.

A spokesperson for DIA said there are cameras around each of its parking lots. Those cameras are not available for the public to see.

It is not clear if they have captured any cars being stolen.