LONDON — Four days after a suicide bombing plunged Britain into mourning, political campaigning for a general election in two weeks resumed Friday with the main opposition leader linking acts of terrorism at home to foreign wars like the one in Libya.
Labour Party leader Jeremy Corbyn risked being assailed for politicizing the Manchester Arena attack that killed 22 people by claiming that his party would change Britain's foreign policy if it takes power after the June 8 vote by abandoning the "war on terror."
"Many experts, including professionals in our intelligence and security services, have pointed to the connections between wars our government has supported or fought in other countries, such as Libya, and terrorism here at home," Corbyn said in his first speech since Monday night's atrocity.
National campaigning had been on hold to honor the victims of the arena bombing.
Salman Abedi, the bomber who struck the Ariana Grande concert, had strong links to Libya. His parents were born and lived there before moving to Britain in the early 1990s. They eventually returned with several of their six children, and Abedi traveled there to visit his family on occasion.
Prime Minister Theresa May, who was attending a summit of the Group of Seven in Sicily, offered a blistering critique of Corbyn's position when she was asked about it at a news conference.
May said that while she was at the summit rallying support for the fight against terrorism, "Jeremy Corbyn has said that terror attacks in Britain are our own fault, and he has said that just a few days after one of the worst terror attacks" in the country's history.
"There can never, ever, be an excuse for terrorism," she said, adding "the choice people face at the general election has become starker."
While Corbyn could alienate some voters with his comments, he is trying to win back the many Labour supporters who turned away from the party in the aftermath of then Prime Minister Tony Blair's decision to join the U.S.-led invasion of Iraq in 2003.
Blair's backing of U.S. President George W. Bush brought more than 1 million protesters into the streets. When the rationale for war failed to pan out because weapons of mass destruction were not found in Iraq, Blair's popularity faded badly after a string of election victories.
When home-grown terrorists attacked London subway and bus lines in 2005, some blamed Britain's involvement in the Iraq war. Corbyn's speech reflects the view that Britain's actions overseas are at least in part responsible for the increase in extremist attacks.
The Labour Party under Corbyn has consistently trailed Prime Minister Theresa May's Conservatives in the polls, but has begun to make gains in the last week. It is unclear how the worst attack in Britain in more than a decade will impact voter sentiment.
British police investigating the Manchester bombing made a new arrest Friday while continuing to search 12 properties.
A total of eight men are being held on suspicion of offenses violating the Terrorism Act. Their ages ranged from 18 to 38.
A 16-year-old boy and a 34-year-old woman who had been arrested were released without charge, police said.
Authorities are chasing possible links between the Abedi and militants in Manchester, elsewhere in Europe, and in North Africa and the Middle East. Britain's security level has been upgraded to "critical" meaning officials believe another attack may be imminent.
Manchester Police Chief Ian Hopkins said substantial progress has been made but detective work remains.
Abedi, a college dropout who had grown up in the Manchester area, was known to security services because of his radical views. His parents came to Britain early in the 1990s.
He reportedly was in contact with family members just before the attack.
The names of the people in custody have not been released. No one has yet been charged in the bombing.
London police say extra security is being added for major sporting events this weekend including the FA Cup soccer final at Wembley Stadium.
Chief Superintendent Jon Williams said Friday extra protection measures and extra officers are being deployed throughout the capital because of the increased terrorist threat level.
He said fans coming to soccer and rugby matches this weekend should come earlier than usual because of added security screening.
Williams said "covert and discrete tactics" will also be in place to protect the transport network.
British police working on the case have resumed intelligence-sharing with U.S. counterparts after a brief halt because of anger over leaks to U.S. media thought by Britain to be coming from U.S. officials.
British officials say that have received assurances from U.S. authorities that confidential material will be protected.
U.S. Secretary of State Rex Tillerson said in London Friday that the U.S. accepts responsibility for the leaks.
At the mosque that Abedi attended in Manchester, director of trustees Mohammed el-Khayat told worshippers that police would be told if anyone shows signs of having been radicalized.
"The police will be the first to know," he said before Friday afternoon prayers. He strongly condemned the attack and said radical views will not be tolerated.
Thamir Nasir, who has attended the mosque for nine years, remembered seeing Abedi there, but said he didn't know him very well.
"This does not represent Islam," Nasir said of the concert bombing. "And it doesn't represent our community, and for sure doesn't represent this mosque here....This center is one of the most open — open to the community. So everyone here is shocked. We could not really sleep that night knowing that this happened in Manchester."
Despite the increased threat level throughout the country, and the addition of extra armed police and soldiers, the country's top counter-terrorism police officer urged Britons not to hide away indoors during the upcoming holiday weekend, which finds much of the country enjoying fine weather.
"Go out and enjoy," Metropolitan Police Commissioner Mark Rowley said.
Rob Harris reported from Manchester. David McHugh contributed from Taormina, Sicily.