U.K. Prime Minister Warns of More Attacks

"We struggle to comprehend the warped and twisted mind that sees a room packed with young children not as a scene to cherish but as an opportunity for carnage," Prime Minister Theresa May said a day after Monday's horrific explosion, which left nearly 60 others injured.

The attack and subsequent intelligence prompted officials to hike the country's threat level to "critical," meaning another attack may be "imminent." Authorities were poised to deploy armed soldiers instead of police at crowded public events as they scramble to piece together information on the accused bomber and the attack.

Authorities said at least 22 people were killed when an explosion went off at the Manchester Arena shortly after an Ariana Grande concert wrapped in the northwestern British city. Eight-year-old Saffie Rose Roussos and Georgina Callander, 18, were among the first victims identified in the deadliest terror attack on British soil since the 2005 London bombings.

ISIS quickly claimed responsibility for the massacre, which officials say was carried out by Salman Abedi, a 22-year-old Brit who died in the attack. Police yesterday raided two sites in Manchester and arrested a 23-year-old man in a third location.

Former Boston police Commissioner Paul Evans, who worked in London as the director of the Police Standards Unit from 2003 to 2007, said the elevated terror threat could indicate authorities suspect Abedi had accomplices.

"By raising the threat level, one would suspect maybe they have other information there are others out there," Evans said. "I would be surprised if there are not a number of individuals arrested. ... Nobody does it better than the Brits, but in a free society, it's incredibly difficult."

Evans, the older brother of current Boston police Commissioner William B. Evans, worked as the Hub's top cop for a decade beginning in 1993. He was in Britain in July 2005 when more than 50 people were killed in a series of coordinated suicide attacks targeting London's transport system.

Authorities released few details on Abedi yesterday, but at least 20 heavily armed police surrounded a modest red brick house listed as his address in a Manchester suburb and blasted down the door. Police also searched an apartment in a nearby area that British media reported belonged to Abedi's brother, Ismail.

Grande has suspended her tour. "Broken. From the bottom of my heart, i am so so sorry. i don't have words," the singer tweeted.

The attack stunned Brits near and far. Harry and Una Palfreyman, who live 30 minutes from where the bomb went off, said they were at the same arena just last month for a concert.

"It's very, very scary," Harry Palfreyman, 69, told the Herald after the couple arrived at Logan International Airport yesterday to visit their son and his family. When they left Manchester yesterday morning, the city was still on high alert, they said, but people had come together to help in whatever way they could.

Taxi drivers gave free rides to people fleeing the carnage, said Una Palfreyman, 68, and people opened their homes to terrified concertgoers.

"You have to be vigilant," she said.

What made the attack particularly horrifying was that it killed or maimed youngsters, some of whose parents were still looking for them yesterday, said Joan Dickinson, who lives in Greater Manchester.

"Why innocent children?" Dickinson, 69, said as she waited at Logan for her flight home. "It's an unbelievable act."

Material from the Associated Press was used in this report.

(c)2017 the Boston Herald