Scrutiny over the gifts and support provided by George Cottrell to Mr. Farage, the Reform U.K. leader, will continue even after he won last week’s special election in Clacton.

Prime Minister Andy Burnham messaged briefly with a person impersonating Susie Wiles, a British government official said.

Emergency services said they were working at the scene of a derailment near Lewes, in East Sussex, on Thursday. Eighteen other people were less badly hurt.

Nigel Farage, the right-wing populist leader, forced a by-election in his parliamentary seat of Clacton after he came under pressure over his financial declarations.