1. The attack claimed many lives: Police say at least 22 people died and at least 59 were wounded after an alleged suicide bomber detonated an improvised explosive device in the foyer area of Manchester arena, as guests were leaving an Ariana Grande concert.
2. People from Manchester are responding with humanitarian gestures: Diversity Officer at University of Manchester Students' Union, Ilyas Nagdee told TRT World. He said the attack was "an instant shock." Free accommodation is being offered to people in the area, he said, while taxi drivers make sure people get home safe offering free rides.
3. Police investigations are ongoing: "With regards to the ongoing investigation into last night's horrific attack at the Manchester Arena, we can confirm we have arrested a 23-year-old man in South Manchester," police said in a statement.
4. Arrests are being made: British police say the attacker died at the scene and are investigating whether he was acting alone. In the meantime they had arrested a 23-year-old man in connection with the attack but there are no details yet. Witnesses said they heard an explosion and rushed for the exits.
5. Daesh claimed responsibility for the attack, and US officials drew parallels to the Bataclan concert hall attack and other sites in Paris, which left 130 dead. This attack is the deadliest in Britain since 2005.
6. Police are treating the incident as a terrorist attack; Manchester Chief Constable Ian Hopkins confirmed that children were among the victims and that at least 19 of those wounded are in critical condition.
7. US singer Ariana Grande has a huge number of young and teenage fans. Desperate parents were searching for their children through social media, sharing photos and pleading for help.
8. The attack comes just before the British elections. Nagdee said there is a possibility that the attack "will be manipulated by political parties for their own use — especially those in the right of the political spectrum."
9. Politicians have reacted immediately: British Prime Minister Theresa May condemned the attack, saying the attacker aimed to cause "maximum carnage." The general election campaigns from both Tories and the opposition Labour Party were suspended.
10. Britain is on its second-highest alert level of "severe," which means that an attack by militants is considered highly likely by the security forces. London's Victoria coach station was briefly closed after discovery of a suspect package.