LONDON – British police have arrested a “large part of the network” behind this week’s Manchester suicide bombing but more arrests are likely, the country’s top counter-terrorism officer said.

Mark Rowley said “immense” progress had been made in the investigation into Salman Abedi who killed 22 people, many of them children, at a concert in Manchester on Monday.

“They’re very significant, these arrests. We’re very happy we’ve got our hands around some of the key players that we are concerned about. But as I say there is still a little bit more to do,” Rowley told broadcasters.

Since the attack, armed police backed up by the army have been patrolling cities and trains. Interior minister Amber Rudd said the threat level remained at its highest level, “critical”, meaning another attack is expected imminently.

Hospitals have been warned to be ready. However, Security Minister Ben Wallace said there was no evidence of a specific threat over Britain’s holiday weekend, when major events will take place including Saturday’s soccer FA Cup final in London, where extra armed officers will be on duty.

People take part in a vigil for the victims of an attack on concert goers at Manchester Arena, in Royton, near Manchester, Britain May 26, 2017. (Photo: Reuters)

As campaigning resumed on Friday for a national election on June 8, the opposition Labour Party, emboldened by a rise in opinion polls, criticised Britain’s foreign policy for increasing the risk of attacks.

He also chided Prime Minister Theresa May for cutting spending on policing.

“We must be brave enough to admit the ‘war on terror’ is not working,” Labour leader Jeremy Corbyn said.

A new poll showed Labour had closed the gap with May’s Conservatives to 5 points, suggesting a far tighter race than previously expected.

Eight people are being held by police following the bombing at the Ariana Grande concert. A further two people who were arrested earlier in the week have been released.

The Guardian newspaper, without citing sources, said three of the 10 people arrested so far were brothers who were believed to be cousins of the bomber, Salman Abedi. His father and two brothers have also been arrested in Britain and in Libya.

Reuters