Federal prosecutors say a Rancho Bernardo man who turned an ATM into a smoking wreck in the middle of the night has now admitted he was behind the blast.
Son Thanh Nguyen pleaded guilty yesterday in federal court to using an explosive device on an ATM outside a First Citizens Bank branch in Rancho Bernardo. According to investigators, the device ignited the machine’s electrical components, sending smoke pouring out for more than 30 minutes and leaving the ATM completely unusable. Surveillance later tied a getaway vehicle to Nguyen, and search warrants reportedly uncovered chemicals and gear consistent with bomb-making. The plea caps a months-long investigation into a pair of early-morning ATM attacks in San Diego.
Federal plea details
In a plea agreement outlined by the U.S. Attorney’s Office, Nguyen admitted that on June 28, 2024, he slid a metal-shaped rod into the ATM’s cash-dispenser slot, wedged in a wired device, and then pulled the wires to trigger the blast inside the machine. The plea was filed in case number 24cr1933-RBM and is being prosecuted by Assistant U.S. Attorneys Andrew Sherwood and Shital Thakkar.
The charge, malicious use of fire and explosive materials to damage property under 18 U.S.C. § 844(i), carries a maximum possible sentence of 20 years in prison and a $250,000 fine.
What happened at the ATM
Surveillance footage and court records show Nguyen drove up to the First Citizens branch in the pre-dawn hours, placed an improvised device into the cash slot, and later circled back to try to grab money once smoke started billowing from the machine, the Los Angeles Times reported.
San Diego Police officers arrived around 3:23 AM to find wires protruding from the ATM and blue material with a valve lying nearby, according to the report. Despite the fiery malfunction and damage, officials say no one was hurt.
How investigators traced the suspect
Investigators leaned hard on the bank’s cameras. The footage captured a clear shot of the vehicle’s license plate, which officers then used to trace the registration back to Nguyen, who was arrested at his Mira Mesa home, NBC 7 San Diego noted.
Authorities also matched other identifying details from the video to Nguyen’s vehicle and, after developing that lead, obtained court-authorized search warrants, according to the outlet.
Search warrants and evidence
When federal agents served those warrants on Aug. 23, 2024, they turned up an assortment of items at Nguyen’s residence: a U-shaped rod, a metal plate welded to a pole, a balaclava, a beanie, gasoline, black powder, potassium nitrate, sulfur, other explosive precursor chemicals, a printed guide on how to make black powder and a firearm, Times of San Diego reported.
Agents also searched his vehicle and recovered a black hose, a neck gaiter, and a California license plate with the number 24876J1, items that investigators say matched what was seen on surveillance footage.
Charges, penalties, and next steps
Nguyen pleaded guilty to malicious use of fire and explosive materials to damage property under 18 U.S.C. § 844(i), the U.S. Attorney’s Office said. The statute carries a potential sentence of up to 20 years behind bars and a $250,000 fine. A sentencing date will be set by the court.
Prosecutors said the FBI led the investigation, with assistance from local bomb-squad and hazmat teams.
How this fits into a wider pattern
Nguyen’s case is part of a broader, unsettling trend: explosive attacks on ATMs across California, ranging from one-off attempts to sophisticated rings that prosecutors say have stolen millions by targeting cash machines.
Coverage of a separate West Coast crew that allegedly used improvised explosives to bust open ATMs shows how some thieves are turning to increasingly risky tactics, ABC7 reported. Local officials note that no one was injured in the Rancho Bernardo blast but say the case is a pointed reminder of how dangerous explosive-based theft attempts can be for the public as well as for would-be robbers.
