NEW YORK (CBSNewYork) — Officials issued a warning for people living in eastern Queens after police say thieves have been targeting mailboxes, hoping to cash in on residents’ stolen mail.

“We don’t put our mail in the mailbox anymore because it’s happening multiple times,” Queens resident Andrew Ferdinandi said.

The NYPD says the thieves steal checks from postal boxes, then forge those check and steal money as part of what they call a “complex scheme.”

“It happened to my wife’s grandma, she noticed a week or two later her account was empty,” Bayside resident Adam Brown said.

Police say dozens of boxes have been hit recently, one even right outside a post office in Bayside.

“You feel it’s safe by the post office but now I won’t,” resident Linda Lacertosa said.

Investigators say they’ve already made one arrest this week, but the thefts can be difficult to trace because oftentimes victims don’t even realize they’ve been targeted until weeks after dropping their checks in the mail.

“You don’t find out until you get a late notice that your bill didn’t get to the destination,” Bayside resident Tina Nomikoudis said.

The 111th Precinct advises people to drop their bills inside the post office to avoid any risk of theft.

“Our USPS mailboxes won’t be secure until they are replaced and have new locks,” the precinct tweeted. The NYPD says the USPS is installing fortified boxes and reining in errant mailbox keys throughout the borough.