In UK, Nineteen people have been killed and about 50 injured in a blast at Manchester Arena, police have said. Witnesses said they heard two loud bangs, reported to be in the foyer, after a pop concert by Ariana Grande. Greater Manchester Police said there are a number of confirmed fatalities and others injured. <br/><br/>The cause of the explosion is unknown but the North West Counter Terrorism Unit is treating it as a possible terrorist incident. BBC Home Affairs Correspondent Daniel Sandford said senior counter-terrorism officers are assembling in London and are liaising with the Home Office. <br/><br/>Manchester Victoria station, which is close to the concert venue, has been closed and all trains cancelled. British Transport Police say explosion was in the foyer area of Manchester Arena.<br/>