At around 10:30 p.m. local time, at the end of a concert by U.S. pop singer Ariana Grande in Manchester Arena, an explosion shook what witnesses described as the foyer area of the venue where merchandise was being sold.
"All acts of terrorism are cowardly attacks on innocent people", Prime Minister Theresa May said, "but this attack stands out for its appalling, sickening cowardice - deliberately targeting innocent, defenseless children and young people who should have been enjoying one of the most memorable nights of their lives".
The US media outlets CBS and NBC identified the attacker as Abedi earlier Tuesday.
Police in Manchester, England, confirm 19 people dead at Manchester Arena following an apparent explosion after a concert by Ariana Grande.
Another man, an unidentified 23 years-old, was arrested on Tuesday in south Manchester in connection the bombing. One other person was arrested at the Arndale Centre, although authorities said it was not immediately clear whether the person was connected with the bombing.
Manchester, 160 miles (260 kilometers) northwest of London, is one of Britain's largest cities and Manchester Arena is one of the world's largest indoor concert venues. They identified the suicide bomber as Salman Abedi, 23, a US law enforcement official told USA Today.
US President Donald Trump spoke with May by telephone and agreed the attack was "particularly wanton and depraved", the White House said.
"Sending love to the U.K., @ArianaGrande and all of her supporters who were caught up in this bad attack".
"It is now beyond doubt that the people of Manchester and of this country have fallen victim to a callous terrorist attack, an attack that targeted some of the youngest people in our society with cold calculation", May said.
Twenty-two people are confirmed dead following the explosion and at least 59 more were injured, several critically.
Saffie Roussos, aged 8, was the youngest of the victims identified so far. Police later said the blast killed 22 people, and over 50 people were injured. "I will call them from now on losers because that's what they are", he said.
"Hundreds of friends, parents, children, and partners are confronting unimaginable grief today, and we send out thoughts to them all", the message said.
A sign saying "Ariana we love you" is left in the street on May 23, 2017 in Manchester, England. She said authorities were trying to determine if he had an accomplice.
After the deadly terrorist attack in Manchester, soccer was the last thing on the minds of Manchester United's players.