Tunisian security forces have arrested the nephew of the Berlin market attacker Anis Amri and two other suspects, officials say.

The Tunisian interior ministry said the three, aged between 18 and 27, were members of a “terrorist cell”, and that they were detained overnight.

Tunisian-born Amri, 24, was shot dead by police near the Italian city of Milan in the early hours of Friday.

Monday’s lorry attack on the market left 12 people dead and 49 injured.