If the police stopped with the military to check documents and suddenly ...?

Good day.

Only police officers can detain a person in order to stop a crime. ** Refusal to receive a subpoena is not an offence, therefore there is no reason for detention**.

If you received a summons, but did not appear at the military commissariat, and if the military commissariat has already created documents regarding the violation of the legislation on military registration or mobilization and sent a request to the police to detain you and bring you to the military commissariat, then only in this case, according to Article 262 of the Code of Administrative Offenses, the police can detain you and take you to the Military Commissariat.

If you are illegally detained, first of all, record everything on your phone (on video or at least a voice recorder). Call the police and report that a criminal offense has been committed against you: abuse of official authority (365 of the Criminal Code of Ukraine), known illegal detention (371 of the Criminal Code of Ukraine).