The official Brexit campaign has been fined £40,000 for sending thousands of unsolicited text messages during the 2016 referendum campaign.

Party must show how it spent £300,000 on data services in run-up to 2016 vote and 2015 election.

Investigation follows revelations of Lynton Crosby firm running ad campaign calling voters to lobby MPs.

Nigel Farage’s Brexit party is being investigated for allegedly failing to answer requests for data it holds on some voters, according to Sky News.