Bouncers at a Mariupol cafa beat Ukrainian State Border Service officials, injuring two, after the latter demanded that they be provided with a menu in the Ukrainian language.

"A lieutenant-colonel of the State Border Service asked for being provided with a menu in the Ukrainian language at a Mariupol cafe, and this prompted the personnel's resistance. A fight started, and a border guard had a jaw broken," Oleh Slobodian, an aide to the State Border Service chairman, said on Channel 5 on Monday.

"The border guards behaved absolutely appropriately and didn't provoke the use of force against them in any way, especially in such an aggressive form," he said.

"Two border guards were injured in the assault, and what's more, one of them is a female officer. The man had a jaw fracture and numerous bruises, and the woman officer suffered the most. She has a concussion and also numerous bruises, and therefore their hospitalization at the Central Clinical Hospital in Kyiv is currently under consideration to examine them more thoroughly and provide them with the necessary medical aid at the stage of eliminating the beatdown effects," Slobodian said.

The assailants' identities are so far unknown, and local police are trying to determine them, he said.

"It is known at the moment that unidentified persons used force against border guards. And this act of aggression was provoked by the border guards' question as to why the establishment didn't have a menu in the Ukrainian language," he said.

"This may indicate deficiencies in Ukraine's information policy," Slobodian said in commenting on the incident.