The gift that a Polish police commander received during a recent visit to Ukraine exploded at police headquarters in Warsaw, slightly injuring the commander and a civilian employee, the Polish Interior Ministry said.

The explosion occurred Wednesday morning at 7:50 a.m. Exactly what object the Polish commander had received as a gift during a working visit to Ukraine was not specified, AP reported.

On Sunday and Monday, the commander met with leaders of the Ukrainian police and the Emergency Situations Service, the ministry said.

After the explosion, "the Polish side has asked the Ukrainian side to provide relevant explanations," the report said.

The police commander has been in the hospital under observation since Wednesday, while the civilian officer did not require hospitalization.