Greece Police’s (EL.AS) anti-terrorism squad has assumed the investigation into an explosion on Thursday that literally destroyed a central Athens apartment and resulted in the death of one man and the serious injury of one woman.

The explosion took place in a nondescript third-floor apartment in the central Ampelokipi district.

According to reports, the fire brigade’s initial findings point to some type of explosive as causing the blast, instead of the usual culprit in such cases, i.e. gas cannisters. Additionally, a handgun was found in the apartment.

Another woman identified as possessing keys to the apartment is now under investigation, while efforts are underway to confirm the identity of the injured woman.

Authorities are investigating the possibility of a bomb-making efforts gone astray.

The owner of the property said he gave the keys to his adult son, and while the latter is in the Netherlands, he gave them to a couple in Athens.