Poland’s interior minister, Marcin Kierwiński, is filing a complaint to prosecutors over an incident that took place under the former government in which a grenade launcher gifted to the then head of police, Jarosław Szymczyk, by a Ukrainian official caused an explosion in Szymczyk’s office.

The incident, which took place in December 2022 and left Szymczyk hospitalised, caused outrage at the time. Pictures later emerged showing that a large hole in the floor caused by the explosion and media reports earlier this month claimed that the resultant repair works cost 17,000 zloty (€3,943).

On Friday, Kierwiński – who took office in December as part of a new government that replaced the former ruling Law and Justice (PiS) party – announced that an audit of the incident “showed 27 very serious transgressions related to the whole story of this grenade launcher and its explosion, 27 transgressions that show the scale of the degeneration of police management by Mr Szymczyk and PiS politicians”.

“Reports will be submitted to the prosecutor’s office in this case,” added the minister. The first will concern possession of a weapon without a permit and the second will relate to abuse of power. Kierwiński said that Szymczyk had failed to have the grenade launched checked after it was gifted to him on a visit to Ukraine.

There was “an obvious failure to fulfil official duties” said the minister, who added that it is “strange” that the previous PiS government did not take any action against Szymczyk. The former police chief was seen as politically close to PiS. He resigned in December a few days before a new government replaced PiS in power.

Szymczyk received two grenade launchers during a working visit to Ukraine on 11-12 December 2022, where he met with the heads of the Ukrainian police and emergency services.

The first – converted into a loudspeaker – was said to have come from the head of Ukraine’s police force, Ihor Klymenko. The second – obtained after a meeting with the head of Ukraine’s state emergency service, General Sergei Kruk – had not been converted but the Ukrainian authorities reportedly assured that the item was safe.

However, as Szymczyk rearranged the grenade launchers at his office in Warsaw after the visit, a powerful explosion occurred. The force of the impact pierced the floor and damaged the ceiling of the room. The effects of the explosion were visible on three floors of the building and Szymczyk was taken to hospital due to injuries sustained.

As a result, the deputy head of Ukraine’s state emergency service, Dmytro Bondar, who was responsible for handing over the gift, was suspended and criminal proceedings were opened in Ukraine.