In late February, a security guard at a U.S. federal office building in Detroit, MI, found a suspicious package. He brought the package into the building, placed it in the lost and found and went on his merry way.

The package sat until March 18, when someone at the office decided to X-ray it to see what was inside. The contents? A bomb that had been there all along, according to ABC News.

The guards on duty immediately notified the Federal Protective Service to have the package moved outside the building. Shortly after it was detonated by Detroit police.

The guard who initially found the package and failed to screen it has since been suspended.

The man charged with planting the bomb is 42-year-old Gary Mikulich, who faces up to 10 years in prison and a $250,000 fine if convicted. A judge has since ordered a mental exam for Mikulich.

[ABC News]