Manchester Terror Attack: US intelligence leaks deeply troubling

US President Donald Trump yesterday described US intelligence leaks over the Manchester bombing as "deeply troubling" and threatened to prosecute those responsible, after a warning by British Prime Minister Theresa May to keep shared data "secure".

In a statement issued by the White House, as Trump joined May at a meeting of Nato allies, he said: "There is no relationship we cherish more than the special relationship between the United States and the United Kingdom."

The British government has expressed its anger at the release in US media of details from the investigation into Monday's concert attack, including photographs of parts of the bomb which left 22 people dead, including children.

Arriving in Brussels, May warned that intelligence sharing with the United States was "built on trust".

"Part of that is knowing intelligence can be shared confidently and I will make clear to President Trump that intelligence shared with law enforcement agencies must be secure," she told reporters.

Visiting the military alliance's new $1.2 billion headquarters with fellow leaders later, Trump led a moment's silence for the victims of what he described as "a barbaric and vicious attack on our civilisation".

In his statement, Trump -- who was already struggling domestically to stem a tide of damaging leaks from law enforcement agencies -- said the information coming out in the US media was "deeply troubling".

"These leaks have been going on for a long time and my administration will get to the bottom of this. The leaks of sensitive information pose a grave threat to our national security," he said.

"I am asking the Department of Justice and other relevant agencies to launch a complete review of this matter, and if appropriate, the culprit should be prosecuted to the fullest extent of the law."

The shellshocked country came to a halt for a poignant minute's silence at 11:00am local time to remember the 22 dead, innocent victims of the latest Islamic State-claimed atrocity to hit Europe.

And as more children were named among the victims of Monday's massacre, Libyan authorities detained the suicide bomber's father as well as his brother while police in Britain carried out fresh arrests and raids.

A spokesman for the Deterrence Force, which acts as Libya's Government of National Accord's police, said the brother was aware of Abedi's plan and the siblings were both members of the Islamic State jihadist group.

Abedi's brother Hashem had been "under surveillance for a month and a half" and "investigation teams supplied intelligence that he was planning a terrorist attack in the capital Tripoli", the Deterrence Force said on its Facebook page.

Emotions were still raw in the northwestern city, three days after Salman Abedi's attack on a concert by US pop star Ariana Grande -- especially so as the bomber was born in the city.

Amid the grief, British authorities were left "furious" by repeated leaks of material shared with their US counterparts.

Images obtained by The New York Times newspaper showed a detonator Abedi was said to have carried in his left hand, shrapnel including nuts and screws and the shredded remains of a blue backpack.

"We are furious. This is completely unacceptable," a government ministry source said of the images "leaked from inside the US system".

The leak, which followed a similar disclosure of the bomber's identity and probe details, has rocked the intelligence-sharing relationship between close allies London and Washington.

The National Counter Terrorism Policing body said the breach of trust caused great "damage" and "undermines our investigations."

The attack was the latest in a series of deadly incidents across Europe claimed by IS that have coincided with an offensive on the group in Syria and Iraq carried out by US, British and other Western forces.

A relative told AFP that Abedi had travelled to Manchester from Libya four days before the bombing.

German police said he had made a brief stopover at Duesseldorf Airport.

French Interior Minister Gerard Collomb has said Abedi had "likely" been to Syria after the trip to Libya, citing information provided by British intelligence services to their counterparts in Paris.

British officials said Abedi had been on the radar of the intelligence community before the massacre.

Police announced two new arrests yesterday in their probe, bringing the total to eight people in custody in Britain. A woman detained on Wednesday was released without charges.

Early Thursday, police said they conducted a controlled explosion in the south of Manchester where they were carrying out searches in the Moss Side area connected to the attack.

Underscoring jitters in the city, bomb disposal units were rushed to a college in Manchester, which later turned out to be a false alarm.

Britain's terror threat assessment has been hiked to "critical", the highest level, meaning an attack is considered imminent.

Armed troops were sent to guard key sites, a rare sight in mainland Britain.

The attack was the deadliest in Britain since 2005 when four Islamist suicide bombers attacked London's transport system, killing 52 people.

The bombing came just over two weeks before a snap general election set for June 8. Campaigning will resume today.

A total of 75 people are being treated in hospital, including 25 in critical care, medical officials said. Twelve of the injured are aged under 16.

One of those killed was eight-year-old .