A suspicious package found Monday outside the MacDill Air Force Base Visitor Center in Florida contained what appeared to be an improvised explosive device, multiple sources told ABC News.
It was not immediately known whether the device would work. The FBI said on Wednesday that it was analyzing the suspicious package, but had so far declined to reveal details about the exact nature of what was found.
In this archive photo provided by the U.S. Air Force dated Jan. 4, 2021, an aircraft hangar is shown at MacDill Air Force Base in Tampa, Florida.
Senior Airman Tiffany Emery/U.S. Air Force via AP, FILE
“A field examination of the contents of the package has been conducted and possible active substances have been identified. Final laboratory analysis has not yet been completed,” the FBI Tampa office said in Post X.
Military officials raised the threat level for the base to FPCON Charlie Tuesday evening, more than a day after the incident. FPCON Charlie is the second highest force protection level out of five levels – indicating a serious threat has occurred and heightened security measures have been taken around the base.
On Wednesday afternoon, a shelter-in-place order was issued after a “threat” against the base, according to officials.
“We take all threats seriously and are taking appropriate actions to prioritize the safety and security of our facilities,” base officials said in a statement.
The shelter in place order was lifted a few hours later.
Tampa Police Department officers and members of the U.S. Air Force block traffic along the South Dale Mabry Expressway after a security threat prompted authorities to order individuals to take shelter at MacDill Air Force Base in Tampa, Florida, on March 18, 2026.
Octavio Jones – Reuters
MacDill Air Force Base is a critical command center for the Pentagon, hosting US Central Command – which directs military operations across the Middle East – as well as Special Operations Command.
Three of the six pilots who died in the crash of a military refueling plane last week in Iraq were stationed there.
ABC News’ Cindy Smith contributed to this report.
