The Army is investigating whether two soldiers were caught up in a Russian-backed plot to discredit British forces after they were set upon by a local gang and then filmed brawling while on exercise in Latvia.

Commanders and Latvian police said they were looking at the incident, but defence sources claimed it appeared to have been a planned attempt to portray British troops as hooligans.

Local media on Wednesday questioned that claim, quoting a relative of one man involved saying drunk British soldiers had started the fight.

The incident came at the end of a fortnight allied training deployment to the Baltic nation and amid strained relations and a war of words between Britain and Russia.