British police are convinced that there is a wider conspiracy behind Monday night's suicide bombing and are racing to uncover it, as the authorities fear another attack could be imminent. Nearly 1,000 armed soldiers have been deployed on the streets.
"I think it is very clear that this is a network that we are investigating," head of Greater Manchester Police Ian Hopkins said yesterday.
The police now believe that the bomber - British-Libyan Salman Abedi, 22 - was just a "mule", and are hunting for a likely bombmaker as well as other accomplices. Abedi is said to have proven links with the Islamic State in Iraq and Syria group.
Yesterday, police arrested three more men after the country went into its highest terror alert just 24 hours after Abedi blew himself up at the end of a pop concert at the Manchester Arena, killing 22 people and injuring more than 60.
It is only the third time that Britain has raised its threat level to the "critical" stage, which means a terror attack is imminent.
The significant move comes as investigators shore up the premise that Abedi, who recently returned from Libya, had help in executing his sophisticated strike.
The three men arrested yesterday live near Abedi's home in south Manchester and are believed to be from Libya. The police also detained Abedi's 23-year-old brother, Ismail, a day after the attack.
Abedi's younger brother, Hashem Abedi, who was born in 1997, was arrested in Tripoli by Libyan counter-terrorism forces.
Meanwhile, troops have moved in to guard key sites in London such as Buckingham Palace, Downing Street, foreign embassies and the Houses of Parliament. This frees up the police to focus on counter- terrorism efforts.
Officers will also conduct more stop-and-search operations and set up vehicle checkpoints, said London police, while up to 3,800 troops could be deployed across the country. Yesterday, more victims of the attack were identified, among them friends Alison Howe, 45, and Lisa Lees, 47, who were waiting for their 15-year-old daughters at the foyer when they were killed by the blast.
Police presence continues to be heavy as Manchester tries to come to grips with what has happened, and that the perpetrator was one of their own.
"It makes me so angry. I am shocked someone who lived in Manchester could do this," said accountant Reena Ghelani, 28, who made her way to a makeshift memorial at Albert Square to lay flowers during her lunch break yesterday.
Laminator John McGrath, 47, a father of four, was less surprised.
"It has always been on the back of our minds that something would happen, but we didn't think it would be a concert that is aimed at the younger generation," he said.
Singaporean researcher Joseph Ong, 26, who recently graduated from the University of Manchester, was in a cinema on Monday night when the lights suddenly came on.
The manager told the audience that there had been an incident at Manchester Arena. The cinema was evacuated, but he discovered the truth only later.
"My first thought was, did I know anyone who was at the concert or could have been near there?" he said, adding that he texted friends to check on them. There are about 300 Singaporeans at the university.
"It was shocking and very saddening to think they would attack children," he said. "I may be Singaporean, but Manchester is my home away from home."
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