As details begin to emerge of the victims, many of whom are known to be children or young adults, the death toll after Monday night’s bombing in Manchester has now risen to twenty-two, according to officials. Fifty-nine people were injured in the blast.

Manchester Police have announced that one person is now in custody under suspicion of involvement. Law enforcement officials have also said they now know the identity of the person who acted as a suicide bomber in the attack, but are not yet releasing that individual’s name.

On Tuesday morning, Ian Hopkins, the Chief Constable of the Greater Manchester Police, gave the following briefing to reporters:

As of this writing, various news outlets—including the Wall Street Journal and the Washington Post—are reporting that the Islamic State (ISIS), using official online channels, has claimed responsibility for the attack.

Though details continue to emerge, police officials in the city of Manchester in the United Kingdom have confirmed that at least nineteen people were killed and many others injured after an apparent bomb exploded at an arena where American pop singer Ariana Grande was playing a concert Monday night.

According to a statement by local police, the incident occurred just before 10:35pm local time. “Police were called to reports of an explosion at Manchester Arena,” the statement read. “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.”

With Grande popular with a younger audience, scenes from inside the arena showed many teenage concert-goers responding to the chaos after the large sound of what witnesses described as an explosion occurred just as the show concluded: