Two British nationals have been detained in northern France on suspicion of planning to join a banned far-right protest, prosecutors have said.
The two men, aged 35 and 50, were arrested near Calais on Sunday after "broadcasting live videos", prosecutor Cécile Gressier told the BBC.
She added that they were detained over "incitement to hatred" and "participation in a group with the intent to prepare acts of violence".
It comes after French authorities last week said they would immediately deport anyone arriving from the UK to take part in planned anti-migrant demonstrations over the weekend.
There had been calls on UK social media for anti-migration activists to take part in a protest in the area of northern France where small boats are launched to carry asylum seekers across the Channel.
