MANCHESTER, UK — At least 22 people died and a further 59 were injured in an explosion at a concert in Manchester on Monday. <br /> <br />Authorities said they were treating the blast as a terror attack until they had further information. <br /> <br />A capacity crowd of 21,000 people were at the Manchester Arena for an Ariana Grande concert, the Guardian reported. <br /> <br />As the show was finishing, there was an explosion in the foyer of the arena. Some witnesses said the attack appeared to be carried out with a nail bomb. <br /> <br />The blast sparked panic inside the arena as thousands of people ran for the exits. <br /> <br />Many of the wounded were reportedly trampled as they ran from the venue. <br /> <br />U.S. officials told Reuters the attack was possibly carried out by a suicide bomber. <br /> <br />However, British police have yet to confirm what caused the blast, and no group has claimed responsibility for the attack.
