The chief commandant of the Polish police, Jaroslaw Szymczyk, who sustained injuries as a result of an explosion at his office in the police headquarters on Friday, said that the blast was the result of an accidental detonation of a grenade launcher that was gifted to him by Ukraine during a working visit to the neighboring state. 

Szymczyk said he accidentally set off a grenade launcher as he was assembling it. Thinking that the device was already used, he placed the launcher in a vertical position which made the grenade launcher unleash a grenade in a room adjacent to his office.

Szymczyk sustained minor injuries and was taken to hospital as a result of the blast.

"When I rearranged the used grenade launchers, which were gifts from Ukrainians, an explosion occurred," Szymczyk told Polish radio RMF FM.  

According to RMF FM, the chief commandant reportedly received two anti-tank grenade launchers as gifts during his visit to Ukraine. The grenade launchers are speculated to be RGW-90s.

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The first was gifted by the Ukrainian chief of police, while the second was gifted by the head of the State Emergency Service of Ukraine, the radio says.

Ukrainian officials have said that the grenade launchers should have already been used.

When Szymczyk came back from his visit to Ukraine, he reportedly wanted to place his gifts in the back of his office. But when one of the grenade launchers was set vertically, it detonated, the radio adds. 

"The explosion was powerful, the impact force broke through the floor, and on the other side, damaged the ceiling," the commandant told RMF FM.  

Warsaw is reportedly asking Kiev for explanations regarding the incident. 

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