A teenager was allegedly put in a headlock and forced to "apologise" for being gay in a homophobic attack on a Tube train.

The 19-year-old man was strangled until he eventually did what his two attackers said because he was struggling to breathe, police claim.

The man and his friends were wearing fancy dress for an event they were attending when they were approached by two youths on a Jubilee line train on a Saturday evening.

The pair are alleged to have verbally abused the victim for being gay and became more aggressive when they were challenged.

British Transport Police (BTP) claim they forced the man into a headlock, snatched his phone and threatened to stab him until he "apologised" for being gay.