TAMPA — For the thief or thieves determined to get away with cash from Tampa Bay ATMs, the third bomb was apparently the charm.

Investigators believe the string of explosions at ATMs in Pinellas in Hillsborough is the handiwork of the same suspect or suspects, Hillsborough Sheriff Chad Chronister said Monday.

In the first two cases, the explosions blew the ATMs to pieces but the culprit wasn’t able to access the cash. The most recent blast, in Valrico on Sunday, did yield some cash. Investigators were still working to determine how much, Chronister said.

The Hillsborough and Pinellas sheriffs’ offices are working with the Bureau of Alcohol, Tobacco and Firearms and Explosives and the FBI to figure out who is responsible. Chronister said he’s worried Sunday’s success will embolden a brazen thief to try again.

“Now that he’s finally accessed some cash, that’s certainly what I’m afraid of,” he said. “How sophisticated, how experienced is this individual, and where does he go from here? We need to get this individual to make sure there’s no more threat to public safety.”

A drive-through ATM at the Regions Bank branch at 3522 Bell Shoals Road in Valrico sits in pieces after a thief blew it up early Sunday and made off with cash, according to the Hillsborough County Sheriff's Office. [ Hillsborough County Sheriff's Office ]

The first explosion happened about 3:20 a.m. on Nov. 4 at the BB&T branch at 3209 Tampa Road in Oldsmar. Deputies responding to an alarm call discovered a drive-through ATM had been blown up, according to information previously released by the Pinellas County Sheriff’s Office. The Sheriff’s Office didn’t say at time whether the suspect got any cash.

The next blast happened three days before Christmas at the Pilot Bank at 12471 Linebaugh Ave. in Tampa. At 3:11 a.m., a male suspect painted exterior surveillance cameras black, including the camera on the drive-through ATM, according to the Hillsborough Sheriff’s Office. A little more than a hour later, at 4:25 a.m., there was an explosion at the ATM. The suspect was not able to access the machine’s safe, deputies said.

Surveillance footage from that scene showed a male suspect wearing a dark blue sweatshirt with an unknown white symbol on the upper chest, black pants and a cloth mask that only revealed his eyes.

The most recent case happened about the same time of the day on Sunday at the Regions Bank at 3522 Bell Shoals Road in Valrico. The suspect painted the lenses of surveillance cameras in the area black, then a blast blew apart a drive-through ATM.

Investigators were working to enhance grainy surveillance footage that was captured from that scene and find out whether nearby businesses have any helpful video.

Chronister said the suspect appeared to be acting alone because surveillance photos and video show one person at the explosion scenes, Chronister said.

But there is also evidence that suggests a second person might be involved.

On July 7, at the same Regions bank hit on Sunday, the ATM camera lens was painted black and the machine tampered with. No explosion occurred and no explosive device was found, but surveillance images show two suspects at the bank on that occasion. A similar incident involving a single suspect happened at the same bank on Sept. 5.

Then, on Dec. 8, a single male suspect painted surveillance cameras black and tampered with the ATM at a fourth bank — a Chase branch at 11650 Countryway Boulevard in the Westchase area — but left without setting of an explosion or accessing the machine.

Investigators say the all of these criminal mischief cases might be connected to the explosions.

Investigators say the male suspect in the center and right images blew up the ATM, left, at the Pilot Bank branch at 12471 W. Linebaugh Ave. on Dec. 22. The unidentified suspect is also believed to be responsible for two other ATM explosions in Pinellas and Hillsborough counties, Hillsborough Sheriff Chad Chronister said. [ Hillsborough County Sheriff's Office ]

Chronister said he was initially concerned the culprit might be detonating the devices remotely, increasing the danger to the public, but he learned Monday the devices are being detonated at the scene.

“I was worried that one of us as innocent bystanders would go to the ATM to access cash and could be inadvertently hurt or killed,” he said.

Chronister could not provide details about the level of sophistication of the explosive devices or the materials used.

He urged the public to report hearing explosions or seeing anything suspicious. In each of the three previous bank blasts, investigators spoke to witnesses who heard what they thought were explosions but didn’t immediately report it. After Saturday’s case, Chronister said, a convenience store clerk in the area thought the noise was an exploding electrical transformer.

“I’m pleading with everybody if you’re out there and you hear an explosion, call the Sheriff’s Office so we can go out and start canvassing the area," he said.

This surveillance image captured on Dec. 8, 2019 at the Chase Bank at 11650 Countryway Blvd. in the Westchase area shows a suspect about to spray paint the surveillance camera on an ATM. Investigators believe this suspect may be involved in a string of recent ATM explosions in Hillsborough and Pinellas counties. [ Hillsborough County Sheriff's Office ]