Celebrities share messages of sadness and support following Manchester explosionThe blast hit the foyer of the building at around 10.30pm. Around 21,000 people are reported to have been at the concert at the time of the explosion. By Staff Reporter May 23, 2017 17:55 +08 The blast hit the foyer of the building at around 10.30pm. Around 21,000 people are reported to have been at the concert at the time of the explosion.