Islamic State has claimed responsibility for the suicide bombing at an Ariana Grande concert in Manchester, UK, which left at least 22 people dead, including children.

Dozens were injured and spread across several hospitals in the city after the attacker detonated an improvised explosive device in the foyer between the entrance to Manchester Arena and Victoria train station. It took place at around 10:35pm as the concert ended and fans poured out.

The Islamist terror group, also known as Isis, had been quiet on social media before and after the attack. But it has now issued a statement through its social media channels claiming to be behind the atrocity.

British security services have not ascribed responsibility for the attack at Manchester Arena on 22 May. Nor have they yet released the identity or motives of the attacker. Isis has been known to opportunistically claim attacks it has no connection to.

"Keep in mind, [Isis] propagandists want nothing more than for the claim to be shared," tweeted Charlie Winter, senior research fellow at the International Centre for the Study of Radicalisation and Political Violence.

"On Manchester, it is crucial to keep in mind that 'IS terrorism' is 'IS propaganda'."

According to Associate Press, a senior intelligence official in the US said they had not yet verified that Isis is responsible for the Manchester attack.

Following the deadly attack, Isis supporters on Twitter and Telegram were celebrating. In its subsequent statement taking responsibility, Isis called the bombing "revenge" for "transgressions against the lands of the Muslims".

It also called the concert venue, attended by thousands of Grande's young fans, "shameless". The statement did not mention the identity of the terrorist.

The first victim of the Manchester attack to be named was 18-year-old Georgina Callander from Leyland, Lancashire. The second was 8-year-old Saffie Rose Roussos also from near Leyland.

Theresa May, the British prime minister, had called the incident a terror attack in a statement made outside 10 Downing Street.

"It's 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 country with cold calculation," May said.

"This was among the worst terrorist incidents we have ever experienced in the United Kingdom. Although it is not the first time that Manchester has suffered in this way, it is the worst attack the city has experienced and the worse ever to hit the north of England."

She added: "Today let us remember those who died, and let us celebrate those who helped, safe in the knowledge that the terrorists will never win and our values, our country and our way of life, will always prevail."

People run through Manchester's Victoria Station following explosions