MANCHESTER, England — An explosion that may have been a suicide bombing killed at least 19 people on Monday night and wounded dozens at an Ariana Grande concert filled with adoring adolescent fans in what the police were treating as a terrorist attack.
Panic and mayhem seized the crowd at the Manchester Arena as the blast reverberated through the building, just as the show was ending and pink balloons were dropping from the rafters in a signature flourish by Ms. Grande, a 23-year-old pop star on an international tour.
Traumatized concertgoers — including children separated from parents — screamed and fled in what appeared to be the deadliest episode of terrorism in Britain since the 2005 London subway bombings.
Prime Minister Theresa May said her thoughts were with the victims and their families in “what is being treated by the police as an appalling terrorist attack.”
There was no immediate word from the police on the precise cause of the blast but unconfirmed reports said it was possibly a suicide bomber who had detonated a nail-filled explosive device.
The scene immediately evoked the terrorist attacks in Paris in November 2015, which included a deadly assault inside the Bataclan concert arena where the Eagles of Death Metal had been playing. But unlike the Bataclan victims, the Manchester concert was filled with young teenagers.