Florida Siblings Indicted After IED Found Outside MacDill Air Force Base

On the evening of March 10, Alen Zheng allegedly planted an improvised explosive device in a secluded location outside MacDill Air Force Base's visitor center in Tampa. Minutes later, officials say he placed a cryptic 911 call stating a bomb had been planted but refused to provide the exact location. MacDill personnel searched the base but did not find the device in the immediate wake of the call. It would sit undiscovered for six days.

On March 11, one day after the bomb was planted, Alen Zheng and Ann Mary Zheng purchased plane tickets to China and sold the vehicle that had been used to transport the device to the base visitor center. The siblings then left for China from Tampa on March 12, though Ann Mary Zheng returned to the U.S. on March 17. Ann Mary was apprehended after returning to the U.S. via a Detroit airport on March 17. Alen Zheng has not returned.

On March 16, a suspicious package was discovered outside the Visitor Control Center at the Dale Mabry Gate of MacDill, which appeared to have "possible energetic materials." The device, which officials noted was potentially "very deadly," failed to detonate. The device was found days later and "safely disassembled," according to the U.S. Attorney's Office for the Middle District of Florida.

Federal prosecutors unsealed indictments on March 26 charging both siblings. Alen Zheng was charged with three counts: attempted damage of government property by explosion, unlawfully making a destructive device and possessing an unregistered destructive device. If convicted, Alen faces a minimum penalty of five years and up to 40 years in federal prison. Ann Mary Zheng faces one count of evidence tampering and one count of accessory after the fact for helping her brother flee and destroy evidence. She faces up to 30 years if found guilty. Ann Mary is being held in the Pinellas County jail and had her first appearance in federal court on March 26, entering a plea of not guilty.

The investigation moved fast once the device was found. Investigators tied Alen Zheng to the phone used to place the 911 call and received footage from Best Buy showing him buying the phone. Ann Mary Zheng is accused of hiding or damaging a 2010 Mercedes-Benz to prevent its use in legal proceedings, court documents show. Despite those efforts, investigators found explosive material in his home as well as residue from the IED in the car he used to transport the device.

Agents spoke with his mother and Ann Mary Zheng, and both said to the agents that Alen Zheng had told them he planted the bomb, according to U.S. Attorney Gregory Kehoe. The pair's mother, who admitted to authorities that her son confessed to the plot, is currently in Immigration and Customs Enforcement custody pending deportation for a visa overstay, but has not been criminally charged.

The siblings are U.S. citizens, Kehoe said, adding that he did not know if they held any dual citizenship. The motive for placing the alleged IED remains unknown, Kehoe said. Kehoe said investigators do not have evidence that a foreign country is connected to the crime and are still investigating Zheng's possible motivations.

The base's strategic significance loomed over the announcement. MacDill Air Force Base is home to U.S. Central Command, U.S. Special Operations Command and the Air Force's Air Mobility Command; Kehoe said the base houses "extremely, extremely important assets for the Department of War that are obviously involved in ongoing operations in the Middle East and elsewhere," a reference to the war with Iran.

FBI Director Kash Patel, posting on X, made clear the bureau intends to reach Alen Zheng wherever he is. "This FBI, working with our partners, will continue pursuing all those responsible and ensure they are brought to justice, no matter where they are," Patel wrote.

Ann Mary Zheng is scheduled to return to court for a detention hearing on March 31 at 2:30 p.m. Alen Zheng remains in China, with no extradition timeline announced.