Updated
Manchester police have arrested a 23-year-old man and raids are being conducted across the city after a suicide bombing at an Ariana Grande concert killed 22 people and injured 59 others.
Police said the 23-year-old was arrested in south Manchester the day after the attack.
Raids were being carried out in the districts of Whalley Range and Fallowfield, where a controlled explosion was carried out.
A number of people remained "very seriously" wounded and more than a dozen children were hospitalised after the attack, health officials said.
The attacker was killed in the bombing.
Grande had just finished performing at the Manchester Arena about 10:30pm on Monday (local time) when there was an explosion outside the venue.
Videos posted to social media showed fans fleeing after the concert and witnesses described "a massive explosion".
8yo, student named among victims
Eight-year-old Saffie Rose Roussos and student Georgina Callander were the first victims from the attack to be named.
Lancashire County Council released a statement saying Saffie was "loved by everyone" and would be "remembered fondly".
Georgina's school, Runshaw College, announced "with enormous sadness" the "health and social care" student was one of the victims in a Facebook statement.
Georgina had tweeted at Grande the day before the concert to express her excitement.
Grande posted on Twitter after the attack, saying she was "broken".
"We mourn the lives of children and loved ones taken by this cowardly act," her manager said in a statement.
Threat level remains high: Theresa May
Speaking outside her 10 Downing Street official residence, British Prime Minister Theresa May said police and security services knew the identity of a suspected suicide bomber who also died in the attack.
Ms May said the authorities were not ready to announce the identity of the attacker.
Ms May condemned the attack as "warped and twisted".
"All acts of terrorism are cowardly attacks on innocent people," she said.
"But this attack stands out for its appalling, sickening cowardice — liberally targeting innocent, defenceless children and young people who should have been enjoying one of the most memorable nights of their lives.
"We struggle to comprehend the warped and twisted mind that sees a room packed with young children … as an opportunity for carnage."
Ms May said the threat level remained severe, meaning "a terrorist attack remains highly likely".
Whole nation shocked: Queen
Queen Elizabeth expressed her deepest sympathy on Tuesday (local time) to all those affected by the attack.
"The whole nation has been shocked by the death and injury in Manchester last night of so many people, adults and children, who had just been enjoying a concert," she said in a statement.
"I know I speak for everyone in expressing my deepest sympathy to all who have been affected by this dreadful event and especially to the families and friends of those who have died or were injured."
In an unrelated incident, police said they arrested a man at a major shopping centre in Manchester after it was temporarily evacuated on Tuesday (local time).
Witnesses said they heard a big bang at the shopping centre, and there were reports of people running from the site.
Police said they did not believe the incident was connected with the attack.
Manchester a 'ghost town'
Brisbane woman Brittney Weller, 20, who lives in Manchester minutes from the arena, said the community was "still very on edge".
"The city centre is like a ghost town," she said.
Ms Weller said she had a sleepless night watching the incident unfold.
"Last night it was terrifying," she said.
"Every 10 seconds or so a different emergency service team would fly down."
Topics: terrorism, law-crime-and-justice, crime, united-kingdom
First posted