Poland’s top policeman said that an explosion in his office was caused by a grenade launcher, telling private broadcaster RMF FM that he had received two of the weapons as a gift from Ukraine.

Poland’s interior ministry and prosecutor’s office had not previously confirmed media reports that the explosion on Wednesday, at police headquarters in Warsaw, was caused by a grenade launcher.

Prosecutors said they were investigating the blast, which resulted in Police Commander in Chief Jaroslaw Szymczyk being taken to hospital.

“When I was moving the used grenade launchers, which were gifts from the Ukrainians, there was an explosion,” Szymczyk told RMF FM.

He said he was moving the launchers into an upright position at the time.

RMF cited a source from a Polish delegation that visited Ukraine as saying Szymczyk had received two launchers from officials as presents during visits to the police and the State Emergency Service of Ukraine.

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