Almost two dozen people died and more than 100 others were injured after a suicide bomber triggered an explosion on Monday night as attendees began to leave one of Grande's concerts in Manchester. He was the son of Libyan parents who migrated to Britain in the early 1990s.
Dagdoug said that the two brothers do consider themselves to be members of ISIS and said that they had been studying ISIS videos online, including instructional videos that teach the viewer how to make a bomb. British police investigating the Manchester Arena bombing arrested a ninth man while continuing to search addresses associated with the bomber.
"We ask at this time that we all continue to support the city of Manchester and all those families affected by this cowardice and senseless act of violence".More news: FA Cup final: Victor Moses doesn't need to apologize - Courtois
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The threat assessment has returned to the level it was at prior to the Manchester attack.
In the letter, Grande apologizes to her fans for what they must be going through while thanking them for their response to the tragedy.
Police have reviewed security at more than 1,300 events over a weekend that includes a number of football matches at Wembley and an athletics meeting in Manchester.
"The only thing we can do now", she continued, "is choose how we let this affect us and how we live our lives from here on out".
Ariana Grande said on Friday that she will return to Manchester for a benefit concert.
Manchester-born Salman Abedi launched the attack on young fans attending a concert by USA pop star Ariana Grande in the latest atrocity claimed by the Islamic State group in Europe. "We won't let hate win", she said.