A series of ATM explosions that appear to be linked are currently being investigated by authorities in Florida. According to NBC News, the Hillsborough County Sheriff’s Office reported the latest explosion happened Jan. 11 at a Regions Bank in the Tampa suburb of Valrico.

A statement from the sheriff’s office said it wasn’t clear how much money was taken. Sheriff Chad Chronister said the explosion was caused by a “bomb-type device,” according to NBC affiliate WFLA. Chronister also said the incident appeared to be connected to two previous ATM explosions – one at a Pilot Bank in Tampa in December and another at a BB&T Bank in Oldsmar, another Tampa suburb, in November.

While the thief couldn’t gain access to the machines’ internal safes and no money was taken in the first two incidents, the sheriff is worried that there will be more incidents now that the person has been able to get cash.