Britain's National Police Chiefs' Council warned Wednesday that leaks of potential evidence "undermine our investigations" and the UK Home Secretary Amber Rudd said she had made it clear that leaks "should not happen again."
The New York Times Wednesday posted photos that show what it reported could be the detonator, a battery, nuts and screws for shrapnel, and fragments of a backpack used in the attack.
A Greater Manchester Police (GMP) spokeswoman did not comment to CNN on the photo publication. The Times, without specifying the source, said British authorities provided access to photos of materials found at the scene.
The incident, which came as concertgoers were preparing to leave an Ariana Grande concert in the city's heart, took the lives of at least 22 people, including several children. Dozens were also wounded in the incident.
The UK will hold a minute of silence Thursday morning at 11 a.m. local time (6 a.m. ET) as the country continues to come to terms with the bombing at Manchester Arena, its worst terror attack since the 2005 London attacks.
The GMP also warned late Wednesday of fraudulent online fundraising for the families of the victims, and pointed Twitter users to a legitimate JustGiving page.
Two more men were arrested early Thursday morning, bringing the number in custody in connection to the bombing to eight. A woman arrested in a raid in Blackley, Manchester, was released late Wednesday without charge, police said.
Raids are taking place throughout the city in what police called a fast-moving investigation after British Prime Minister Theresa May raised the terror threat to its highest level -- critical -- for the first time in a decade.
Salman Abedi, a 22-year-old British-born national of Libyan descent, was named by police as the suicide bomber in Monday's attack, and investigations are underway to uncover his associates.
"It is very clear that this is a network we are investigating," Greater Manchester Police Chief Constable Ian Hopkins said.
Almost 1,000 soldiers have been deployed to guard key locations around the UK, including Buckingham Palace, to free up armed police to conduct extra patrols.
Up to 3,800 military personnel would be available to support police, Home Secretary Rudd said, amid warnings of another potential attack.