Polish police chief Jaroslaw Szymczyk said on Saturday that the “gift” he had brought from Ukraine was an anti-tank grenade launcher, which exploded causing minor injuries.

On 11 and 12 December, Szymczyk made a working visit to Ukraine, where he met with officials from the country’s police and emergency services.

According to the Polish Ministry of Internal Affairs, “The gift came from one of the heads of the Ukrainian services.”

On Saturday, the Polish police chief told RMF radio that the gift consisted of two grenade launchers, one of which was shaped like a loudspeaker.

Szymczyk was told the guns were safe, but one exploded on Wednesday, causing minor injuries. It is not yet known what caused the gun to explode.

“The explosion was powerful, it punctured a hole in the floor and damaged the ceiling,” Szymczyk detailed.

An investigation is ongoing to determine responsibility for the incident.