Ariana Grande concert attack in pictures

Medics deploy at the scene of a reported explosion. PIC/AFP.

PIC/AFP.

Police deploy at scene of explosion in Manchester, England, on May 23, 2017. PIC/AFP.

The tour began in Phoenix, Arizona, in February. After Manchester, Grande was to perform at venues in Europe, including Belgium, Poland, Germany, Switzerland and France, with concerts in Latin America and Asia to follow. PIC/AFP.

The Dangerous Woman tour is the third concert tour by 23-year-old Grande and supports her third studio album, "Dangerous Woman." Grande's role as Cat Valentine on Nickelodeon's high school sitcom "Victorious" propelled her to teen idol status, starting in 2010. PIC/AFP.

There was no immediate claim of responsibility for the attack. Online, supporters of Islamic State, which holds territory in Iraq's Mosul and around its de facto capital in the Syrian city of Raqqa, celebrated the incident. One wrote: "May they taste what the weak people in Mosul and (Raqqa) experience from their being bombed and burned," according to the U.S.-based SITE Intelligence Group.

Police advised the public to avoid the area around the Manchester Arena, and the train station near the arena, Victoria Station, was evacuated and all trains canceled. (INFO/AP)

Video from inside the arena showed concertgoers screaming as they made their way out amid a sea of pink balloons. (INFO/AP)

"A huge bomb-like bang went off that hugely panicked everyone and we were all trying to flee the arena," said concertgoer Majid Khan, 22. "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." Added Oliver Jones, 17: "The bang echoed around the foyer of the arena and people started to run." (INFO/AP)

Britain's terrorist threat level stands at "severe," the second-highest rung on a five-point scale, meaning an attack is highly likely. If the incident is confirmed as a terrorist attack it would be the deadliest in Britain since four suicide bombers killed 52 London commuters on three subway trains and a bus in July 2005. (INFO/AP)

Jenny Brewster said she was leaving the concert with her 11-year-old daughter when the blast hit. "As I turned around, boom, one loud noise," she told Sky News. "A gentleman said 'run!' so we ran." Outside, she said, "you could smell the burning." (INFO/AP)

The incident led to a nightlong search for loved ones as parents tried to locate their teenage children and groups of friends scattered by the explosion sought to find one another. Twitter and Facebook were filled with appeals for information about people who had not been accounted for. (INFO/AP)

Manchester Arena said on its website that the blast struck outside the venue as concertgoers were leaving. Some eyewitnesses said it happened in the foyer of the arena just after the concert ended. One witness said Grande had just finished her final song and said "Thank you, Manchester," before leaving the stage. (INFO/AP)

There was panic after the explosion, which struck around 10:30 p.m. (2130GMT) as Grande was ending the concert, part of her Dangerous Woman Tour. Grande, who was not injured, tweeted hours later: "Broken. From the bottom of my heart, I am so so sorry. I don't have words." (INFO/AP)

Police cars, bomb-disposal units and 60 ambulances raced to the scene as the scale of the carnage became clear. "We are currently treating this as a terrorist incident until we know otherwise," said Ian Hopkins, chief constable of Greater Manchester Police. (INFO/AP)

Greater Manchester Police said 19 people were confirmed dead after the explosion at Manchester Arena. Northwest Ambulance Service said 59 injured people had been taken to hospitals, and a number of "walking wounded" were treated at the scene. (INFO/AP)

An explosion struck an Ariana Grande concert attended by thousands of young music fans in northern England's Manchester late Monday, killing at least 19 people and injuring dozens in what police were treating as a terrorist attack. (INFO/AP)