Manchester explosion: Here's what we know about the victims

There are reports of 20 or more dead - and multitudes injured - as the result of a series of explosions that hit Manchester Arena in England just as an Ariana Grande concert was finishing Monday.

A witness who attended the concert said she felt a huge blast as she was leaving the arena, followed by screaming and a rush by thousands of people trying to escape the building. Emergency vehicles were helping the injured and bomb disposal units were later seen outside the venue.

News reported that police warned people to avoid the area around the venue amid reports of an explosion around 10:35 p.m. local time.

Manchester Chief Constable Ian Hopkins said police were treating the blast as a terrorist incident and were working with counter-terrorism police and intelligence agencies but gave no further details on their investigation.

Ariana Grande tweeted: "broken. from the bottom of my heart, i am so so sorry. i don't have words".

"As I turned around, boom, one loud noise", she told Sky News.

Jordan Thorpe, 21, from Glasgow, who had been to the concert with his friend Victor Iliev, 22, told i: "I videoed the last song. We obviously then run to try and find our children and fortunately for us we were all safe to tell the story".

"Ariana was off the stage, she'd finished her set", he said.

Britain is on its second-highest alert level of "severe" meaning an attack by militants is considered highly likely.

Chicago police are "closely monitoring the incident in Manchester and we are in real-time communication with our federal partners", the department said in a statement.

"A huge bomb-like bang went off that hugely panicked everyone and we were all trying to flee the arena", he said.

Added Oliver Jones, 17: "The bang echoed around the foyer of the arena and people started to run".

British Prime Minister Theresa May is due to chair a meeting of the government's COBRA emergency committee later Tuesday. She and other candidates suspended campaigning for Britain's June 8 election after the blast.

The attack - for which the Islamic State later asserted responsibility - killed 89 people and injured hundreds more, becoming the deadliest event on French soil since World War II.

Paula Robinson, 48, from West Dalton about 40 miles east of Manchester, said she was at the train station next to the arena with her husband when she felt the explosion and saw dozens of teenage girls screaming and running away from arena.

The Dangerous Woman Tour is the third concert tour by Grande and supports her third studio album, "Dangerous Woman".

Grande is a 23-year-old pop singer and actress who has been in the public spotlight since 2010, when she began appearing on the Nickelodeon television show "Victorious". The tour began on February 3, 2017, in Phoenix, Arizona at the Talking Stick Resort Arena. She was scheduled to perform in England, Belgium, Poland, Germany and Switzerland. More than 200 people were injured, though no one was killed.

  • Zachary Reyes