Police have confirmed 19 people have died following an ''explosion'' at an Ariana Grande concert.

It has been revealed that there have been ''a number of fatalities'' at Manchester Arena in north west England following the singer's performance at the venue and over 50 people are also injured.

In a statement on Twitter, police said: ''Further details on the incident at Manchester Arena have now been released. Just before 10.35pm on Monday 22 May 2017, police were called to reports of an explosion at Manchester Arena.

''So far 19 people have been confirmed dead, with around 50 others injured. This is currently being treated as a terrorist incident until police know otherwise.''

A statement by the British Transport Police says the explosion happened ''within the foyer area''.

The statement reads: ''Officers are at Manchester Arena following reports of an explosion within the foyer area of the stadium at 10.30pm this evening.

''Emergency services are at the scene and we are working to establish more information regarding the explosion and will provide further updates as soon as possible.

''Please avoid the area whilst emergency services continue to respond to this incident. No trains or trams are running from Manchester Victoria station.''

Greater Manchester Police and other emergency services are continuing to work at the scene.

They wrote on Twitter: ''Emergency services continuing to work at the scene of incident. Please continue to avoid the area and follow @gmpolice for updates ... We are working to provide a number for anyone concerned about loved ones to contact which will be released as soon as possible (sic)''

Concertgoers reported hearing a ''loud bang'' at the back of the venue.

Calvin Welsford said: ''I was in the front row and it seemed to happen at the very back of the arena. It almost sounded like a gunshot. That's how I would describe it. It was very loud.

''I looked around and people were just spilling down, heading out of the building. I was actually having an asthma attack. It was sheer panic. Security told us we needed to leave but they were very caring. People were crying.''