“There was so much material left behind that it clearly could have been turned into at least one other bomb,” the official said.
The British home secretary, Amber Rudd, said on Friday that the alert level would remain at “critical” — meaning another attack “is expected imminently” — at least through the weekend. But public events, including the Great Manchester Run, a 10-kilometer race and half-marathon in the city that is scheduled for Sunday, will take place as planned.
“The police have been engaging with organizers of events to ensure they get all the support at those events that people want to have, and they may see some additional military presence,” Ms. Rudd said. “But I hope they will take comfort from that and they will feel more secure. We must not let this terrible terrorist incident impact on our lives.”
Ms. Rudd and Prime Minister Theresa May, among other British officials, have expressed frustration with the American government after several news organizations, including The New York Times, published details of the investigation. President Trump expressed outrage over the leaks on Thursday and called for a Justice Department investigation.
On Friday, Secretary of State Rex W. Tillerson, on a visit to London to meet Britain’s foreign secretary, Boris Johnson, said the United States accepted full responsibility for what had happened. The Manchester police, who had said that they would stop sharing information…