"They communicated to DHS as well as other USA government agencies their concern over leaks about their investigation into the incident in Manchester - information that's gotten into the press and public through United States sources when the UK was leading the investigation and wants to protect the information", Lapan said.
The row - which goes to the heart of the close intelligence-sharing relationship between the transatlantic allies - provides an awkward backdrop to the Prime Minister's meeting with President Trump at the North Atlantic Treaty Organisation summit in Brussels.
The Manchester attack has caused revulsion across the world because it targeted children and teenagers, who make up the bulk of Grande's fan base.
"Home Secretary says she's "confident" the leaks about Manchester attack to USA media will now end", BBC political correspondent Vicki Young said on Twitter, referring to the interior minister by the commonly used title in Britain.
Britain ordered soldiers to key sites on Wednesday and raised the terror alert to maximum after the Manchester concert suicide bombing by a local man of Libyan origin who may have been radicalized in Syria.
British police and security services are also upset that the name of British bomber Salman Abedi was apparently leaked by us officials and published while police in Britain were withholding the name for operational security.
Several media outlets, citing British officials, have stated that the bomb used at the concert was much more sophisticated than those generally employed in lone-wolf attacks.
A woman arrested in the Blackley area of Manchester yesterday has been released without charge.More news: American arms deal with Saudis is under fire in Israel
More news: Manchester concert bombing victims identified
More news: Cavaliers rebound with Game 4 win over Celtics
Armed police patrolled outside St. Paul's Cathedral in London, another popular tourist spot.
France's interior minister said Abedi is believed to have travelled to Syria and had "proven" links with the Islamic State group.
Despite Rudd's urging, information about Abedi's family and means of his identification continued to emerge Wednesday.
"We are furious. This is completely unacceptable", a government ministry source said.
"These searches are connected to Monday's attack on the Manchester Arena, but this is a fast-moving investigation and we are keeping an open mind at this stage", the Greater Manchester Police force said in a statement.
The detonator also appeared to have a small circuit board inside it, the Times said, which may have linked it to the backup detonation system. "The issue is being raised at every relevant level by the British authorities with their U.S. counterparts".
Citing unnamed federal security sources, Focus reports that British-born Salman Abedi twice flew from a German airport in recent years and wasn't on any worldwide watch list. Officers also raided a property in the city's Moss Side neighborhood early Thursday and carried out a controlled explosion. Grande was scheduled to perform in London tomorrow night and Friday, before crossing the English Channel for shows in Belgium, Poland, Germany, and Switzerland.
Katz reported from London.