The Arizona State Courts Building in downtown Phoenix shut down for a day in early January after a suspicious package surfaced in the mailroom, sparking fears of a homemade bomb. State officials now say the scare turned out to be a dud, with the Arizona Department of Public Safety announcing Thursday that the item contained no explosive material and closing the investigation.
The episode started on Jan. 6, when initial field tests on a parcel delivered to the court’s mailroom flagged possible explosive material. Officers reported finding multiple small vials inside that gave positive readings for a homemade explosive substance, which triggered evacuations of the State Courts Building and nearby state offices. The courthouse, which houses the Arizona Supreme Court and Division One of the Court of Appeals, was closed while safety sweeps were carried out and the package was moved offsite for further analysis, as reported by CBS News.
Arizona’s Family Investigates later reviewed a Phoenix Police Bomb Squad report showing that early screening picked up hexamethylene triperoxide diamine (HMTD), a highly sensitive explosive compound. But the Department of Public Safety told Arizona's Family on Thursday that follow-up laboratory testing found no evidence of explosive material in the parcel. The package also contained an illegible letter believed to have been written by a man in Florida. DPS said investigators were not able to locate that person and, with no confirmed explosives, the agency closed the case.
How investigators handled the package
Once staff raised the alarm, the Phoenix Police Bomb Squad teamed up with federal partners to isolate the parcel, then moved it to the city’s bomb squad explosive disposal range for controlled analysis and disposal. Streets and several state offices near the Capitol Mall were shut down during the response while technicians conducted safety sweeps and transported the package in a secure vehicle, according to local reporting. AZPM highlighted the coordinated, multi-agency response at the scene.
Why a trace positive triggers big responses
Federal assessments have long flagged compounds such as HMTD and TATP as unstable homemade explosives that are highly sensitive to heat, shock or friction. That is why even a trace positive on a field test can bring an entire government complex to a standstill while specialists move in. A 2010 U.S. Government Accountability Office technology assessment explains that some homemade explosives can be made from common materials and that trace- and kit-based screening must be backed up by careful lab analysis, underscoring why authorities treat any positive detection as a serious threat (GAO).
Legal status and next steps
DPS told Arizona's Family that, because no explosives were confirmed and investigators could not find the man believed to have sent the parcel, the agency closed the investigation with no charges reported. Court operations have since resumed at the State Courts Building, though the incident underscored how sensitive courthouses and civic mailrooms remain to anything that looks even remotely suspicious.
Officials say they will continue to follow standard mailroom screening and emergency protocols to protect staff and the public. Anyone with information about suspicious deliveries to state offices is asked to contact local law enforcement.
