Greater Manchester Police say there are a number of confirmed fatalities and injuries following reports of an explosion at Manchester Arena.
Witnesses reported hearing a "huge bang" at the venue during an Ariana Grande gig and police have warned people to stay away from the area.
Greater Manchester Police tweeted a statement urging people to avoid the area as "first responders work tirelessly at the scene".
Police statement on incident at Manchester Arena pic.twitter.com/gaKASukx9a
— G M Police (@gmpolice) May 22, 2017
Emergency services responding to serious incident at Manchester Arena. Avoid the area. More details will follow as soon as available
— G M Police (@gmpolice) May 22, 2017
Rail lines out of Manchester Victoria Station are blocked, according to Network Rail.
The area around the arena was swamped with police and emergency services. Approach roads have been closed by police.
Witnesses said they heard two loud bangs inside the arena and coming from where the bars are located.
A spokesperson for the pop singer said: "Ariana is okay. We are further investigating what happened".
Suzy Mitchell whose flat is opposite the venue, reported a huge bang rocking the neighbourhood.
She told the Press Association: "(I) just heard a huge bang from my bed, came out to the front of my apartments (we're on the top floor so have perfect view) and everyone was running away in big crowds.
"The bang was so big I heard it from my room which is at the back of the apartment blocks.
"Currently lots of emergency services going to and from. But can't see anything substantial as of yet except fleeing people and lots of cars."
One fan at the concert described how the explosion hit the venue as fans were leaving the building.
Majid Khan said: "I and my sister, along with a lot of others were seeing Ariana Grande perform at Manchester Arena, and we were all exiting the venue when around 10.40-10.45pm-ish a huge bomb-like bang went off that hugely panicked everyone and we were all trying to flee the arena.
"It was one bang and essentially everyone from the other side of the arena where the bang was heard from suddenly came running towards us as they were trying to exit Trinity Way and that was blocked so everyone was just running to any exit they could find as quickly as they could.
"Everyone was in a huge state of panic, calling each other as some had gone to the toilet whilst this had gone off, so it was just extremely disturbing for everyone there."
Witnesses reported helicopters were circling above the scene after reports of the blast.
