Belarus stated they are sending 5 battalion-tactical groups to the border with Ukraine 

The Ministry of Defense of Belarus reported this.

“Currently, in accordance with the task set by the Commander-in-Chief of the Armed Forces, five battalion tactical groups together with the border guards are covering the southern borders of our country to prevent various nationalist armed groups from entering the Republic of Belarus, illegally delivering weapons, ammunition and explosives,” said the Minister of Defense Viktor Gulevich.

Also the message said it is planned to replace these groups with the same units soon.