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Troops deployed to deal with terror threat

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The UK's terror threat level has been raised to "critical", the highest possible rating, with military personnel being deployed to protect key sites against potential further attacks. The government's move comes after investigators were unable to work out whether Manchester bombing suspect Salman Abedi worked by himself or had assistance.

BBC security correspondent Frank Gardner says the number of troops deployed will be in the hundreds, not around the 5,000 figure reported.

Four of the 22 people killed in Monday's bombing at the Manchester Arena have been named. They are Olivia Campbell, 15; eight-year-old Saffie Rose Roussos; Georgina Callander - thought to be 18; and John Atkinson, 28. Several people are still missing and the 59 injured include 12 children under the age of 16.

We'll have the latest updates on the investigation on our live page.

Analysis: How did the bomber do it?

Dominic Casciani, home affairs correspondent

Most jihadists discount a bomb attack at the early stages: they realise that it's too difficult to pull off. They might accidentally kill themselves while making the device. Their purchasing patterns might raise suspicions in a local pharmacy or, online, prompt GCHQ to have a closer look at their digital life. They may turn to someone else for help who, unbeknown to both, is already on the MI5 radar.

Read Dominic's full article

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Terror arrest at Stansted

A 37-year-old man has been arrested at Stansted Airport on suspicion of preparing for acts of terrorism. Police suspect the man, who had been due to board a plane to Turkey, had been planning to travel to Syria. The arrest is not connected with the Manchester bombing, Scotland Yard says.

Trump meets Pope

They've clashed over issues including migration and climate change, but US President Donald Trump and Pope Francis are coming face to face, as they hold a meeting in the Vatican City. "It is hard to think of two more contrasting characters," says BBC North America editor Jon Sopel, but "both men will be seeking to find common ground".

Trump-Russia inquiry 'well-founded'

He's away, but Donald Trump's domestic woes haven't disappeared, with former CIA director John Brennan saying the investigation into possible collusion between officials on his election campaign and Russia is "well-founded". He told the House Intelligence Committee the Kremlin had "brazenly interfered" in last year's election but he did not know if the Trump campaign had intrigued with Moscow. Mr Trump has called the investigation a "charade".

What the papers say

"Killed by evil" says the Mirror's headline, calling those who died in the Manchester bombing the victims of "grotesque barbarity". The Daily Mail claims an "Islamist terror cell may be on the loose", and the Guardian says Salman Abedi was known to police but had been regarded as a peripheral figure.

Daily digest

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Today's lookahead

Today Donald Trump heads to Brussels later, as his first overseas tour as US president continues.

09:00 Taiwan's Constitutional Court issues its decision on whether the current ban on same-sex couples registering their marriage is illegal.

19:45 Manchester United take on Ajax in the final of the Europa League, in Stockholm, Sweden.

On this day

1988 Section 28, banning councils and schools in England and Wales from intentionally promoting homosexuality, comes into force.

1995 Former Labour Prime Minister Harold Wilson dies, aged 79.

From elsewhere

£400m a year spent on excess baggage charges (Daily Mail)

Undocumented student's seven-year drama (New Yorker)

How Sherpas have evolved superhuman energy efficiency (Cambridge University)

Should adult children living at home pay board? (Sydney Morning Herald)

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