Britain's politicians resume campaigning in earnest on Friday with national security thrust into the spotlight as police scramble to bust a Libya-linked jihadist network thought to be behind the Manchester terror attack.
Prime minister Theresa May and Labour leader Jeremy Corbyn had suspended campaigning after Monday's suicide bombing at a Manchester pop concert, which killed 22 people, including many teenagers, and wounded dozens more.
Eight suspects are currently in detention on UK in connection with the blast, for which the Islamic State has claimed responsibility, while police in Libya have detained the father and brother of 22-year-old suicide bomber Salman Abedi.
Police said a man was arrested in the Moss Side area of Manchester in the early hours of Friday and another man held earlier was released without charge.
Washington's top diplomat Rex Tillerson is due to visit London later on Friday in an expression of solidarity, after Britain reacted furiously to leaks of sensitive details about the investigation to US media.
US president Donald Trump threatened to prosecute those responsible for the "deeply troubling" security breach, which has strained the close relationship between Washington and London.
At a summit of NATO allies in Brussels on Thursday, May confronted Trump over the issue, saying shared intelligence "should be kept secure".
Monday's bombing at a pop concert was the latest in a series of IS-claimed attacks in Europe that have coincided with an offensive on the jihadist group in Syria and Iraq by US, British and other Western forces.
Britain's terror threat assessment has been hiked to "critical", the highest level, meaning an attack is considered imminent.
Troops have also been sent to guard sensitive sites, an unusual sight in mainland Britain, while armed police are now patrolling the country's trains for the first time.
The issue of security, which was not widely discussed in the election campaign before the attack, is now expected to feature highly.
At the launch of the UK Independence Party's manifesto on Thursday, deputy leader Suzanne Evans said that May, a former interior minister, "must bear some responsibility" for the terror attack in Manchester this week due to policing budget cuts.
Opposition leader Corbyn in a speech in London later on Friday is also expected to say it is the "responsibility" of governments to minimise the risk of terror by giving police the funding they need.
Corbyn, a veteran peace campaigner, is also set to link British foreign policy to domestic terrorism, saying that Labour would "change the way we do things abroad" if it wins power.
"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 and terrorism here at home," Corbyn will say.
A YouGov poll published in Friday's edition of The Times put the Conservatives on 43 percent compared to Labour on 38 percent, far better for Labour than the double-digit margin that had previously separated it from the ruling party.
However, the poll also suggested that 41 percent of respondents believe the Conservatives would handle defence and security best, compared to 18 percent who said the same of Labour. YouGov polled 2,052 people on Wednesday and Thursday.
Updated Date: May 26, 2017 13:47 PM