Newspaper headlines: Hunt for 'new Jihadi John', Saudi-Iran tensions and Stokes' record-breaking 258
The release of a video by the Islamic State group purporting to show the killing of five men it accused of spying for UK intelligence in Syria features on the front pages - and there is much interest in the masked man with a British accent in the footage.
The Daily Mail is among a number of papers to suggest the clip shows the emergence of a "new Jihadi John" figure.
According to a forensic analyst quoted in the Times, the man was most likely to be of south-east Asian heritage, born in the UK and from southern England. His taunting of the prime minister and directions echo that of Mohammed Emwazi, the London man originally dubbed Jihadi John, who died in a drone strike in November, it adds.
MI5 agents are urgently working to establish his identity, says the Daily Telegraph, amid concern that the video might signal the start of a new IS propaganda campaign in the wake of Britain's decision to join coalition airstrikes in Syria.
But writing in the Sun, former SAS officer Andy McNab says the video is a sign of desperation following the defeat of IS in the Iraqi city of Ramadi.
The Sun's headline is "Jihadi Junior" - its story focuses on a young boy in the video with a British accent who talks about killing "non-believers". In a leading article, the Sun says: "The depraved mindset which uses a young boy in a murder video to threaten more terrorism deserves nothing but contempt".
The Daily Mirror says featuring the boy in the shocking video is a "horrifying new low" for IS but the footage "reminds us they remain barbaric and are far from beaten".
In the Guardian, Martin Chulov says the identity of the masked man in the video "will likely be quickly established by British security services who... have compiled exhaustive lists of citizens who have travelled to Iraq and Syria".
The boy in the video, he suggests, is not necessarily one of the British children who have been taken to Syria by their families - "he could easily be a Syrian or Iraqi who has picked up some English".
- Dirty dozen to be cleaned for Queen's 90th birthday - The Times reports that a national campaign is to ask the public to identify 12 places in the UK in need of a tidy before the monarch's big day in April
- Lemmy: Bond legend could be me in film - The Daily Mirror says the late Motorhead frontman wanted Roger Moore to play him in a screen biopic
- Court TV succeeds without a celebrity judge in sight - The Independent charts the most popular hearings in the Supreme Court's online video archive. An £85 parking penalty appeal case that went all the way to the top of the judiciary has proved the most popular case to date
- Hundreds of police paid for by business and parishes - The Daily Telegraph reports that more than 1,100 police and community support officers in England and Wales are being funded by residents, schools, councils and shopping centres
- Duke shows young royals that he is the King of Style - The Daily Express reports on an "unlikely candidate" in GQ magazine's list of 50 best dressed men for 2016. At number 12, Prince Philip is 26 places above his grandson, Prince Harry
Photographs of protests in Iran following the execution in Saudi Arabia of a prominent Shia Muslim cleric and 46 other men accused of terror-related offences feature in many papers. And the story attracts the attention of the leader writers.
Saudi Arabia has severed diplomatic ties with Iran.
By most assessments Sheikh Nimr al-Nimr was a dissident, not a terrorist, says the Times, and the concerns he raised about Shia minorities in Saudi Arabia will need to be addressed if the country's status quo is to survive. Britain, as an ally, should be helping Riyadh to reform while preserving the regime's stability, it says.
In the Guardian's view, there is unlikely to be any head-on military confrontation between Saudi Arabia and Iran. Yet the situation "must worsen what is already a toxic relationship. It could also weaken pragmatists and inflame internal differences in both countries at a time when efforts to bring about settlements in Syria and Yemen need all the help they can get".
The lead story in the Independent reports criticism by the Liberal Democrats and other opposition MPs of the close relationship between the UK and Saudi Arabia in the face of concerns over human rights abuses in the kingdom.
The paper says the execution of Sheikh Nimr al-Nimr marks another low in relations between the "Middle East's two blood enemies". The Riyadh regime is in many ways revolting, "but it is not in our interest to see, let alone provoke, the fall of the House of Saud... the Saudis need to be made aware that if they are to survive, they must mend their ways", says the Independent.
What the commentators say...
The achievements of England cricketer Ben Stokes are hailed after his record-breaking double century in the Second Test against South Africa in Cape Town.
His 258 included reaching 200 in 163 balls, the fastest by an England batsman, and stunned South Africa, says the Daily Express.
Stokes, whose 11 sixes were also the most by an England batsman in a Test innings, played a "blizzard of magnificent strokes... pure and pitiless at the same time... unforgettable cricket", writes Mike Atherton in the Times.
The Sun says the 24-year-old Durham all-rounder "redefined what is possible", breaking a number of other records and "several pages of Wisden were put through the shredder".
And for one onlooker, reports the Daily Telegraph, Stokes's antics were the culmination of an anonymous gift. The mystery benefactor had sensed potential greatness in the then 13 year-old and funded coaching at Cockermouth Cricket Club in Cumbria to iron out flaws in his batting and bowling, it reports.
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