Newspaper headlines: 'Slaughter on sunbeds'
Horrific images of dead holidaymakers lying on the white sand of the beach at Port El Kantaoui in Tunisia cover much of the national press.
While details are still unclear as the overnight print editions roll off the presses, it seems likely that a gunman dressed in black shorts and T-shirt arrived at the packed beachside - possibly from a dinghy - and after briefly reconnoitring the area began firing at tourists.
The man - named in a number of papers as 23-year-old Tunisian student Seifedinne al-Razqy - was later shot dead by security forces, but at least 38 others were killed in the rampage. At least five of the dead are British.
It is not yet known if he had any accomplices, but at least two other men are pictured in various publications being detained by police in the resort.
The Daily Telegraph says the gunman smiled and laughed as he walked the beach selecting targets from Western tourists, and reportedly telling locals to leave the area.
The Times says his 20-minute rampage began when he dropped a beach parasol to reveal a Kalashnikov, but many tourists mistook his first shots for fireworks, and it was a while before mass panic set in with people rushing to the sea or the nearby hotels.
Among the witness reports in the papers are Tony Callaghan, a policeman from Norfolk, who recalls: "I used to be in the RAF, I know the sound of gunfire, I shouted to everyone 'this isn't a fireworks display you need to get yourself to safety now'."
He tells the paper of encountering dazed elderly holidaymakers wandering around amid "incessant gunfire".
Despite Mr Callaghan's efforts to hide in the hotel, both he and his wife Christine received gunshot wounds.
Another former military man, ex-Gurkha officer Keith Hawkes of Somerset tells the paper his military training kicked in and he ran towards the gunman, passing him by a matter of feet before seeking refuge with his wife in a hotel.
Mr Hawkes, 70, says: "Why he didn't shoot me, I'll never know.
"I'm an ex-military guy so I've seen it all before, but this was absolutely terrible... a cowardly, cowardly act."
The Daily Mirror says the attack has prompted a mass exodus by many of the 20,000 British tourists believed to be in Tunisia at the moment.
The paper says many large holiday companies were arranging extra flights from the North African country and were allowing those due to set off for there, the opportunity to change destinations.
Amid the wide scale coverage of the Tunisia murders, the news of an apparently jihadist inspired attack in France, and a mosque bombing in Kuwait gets pushed on to inside pages.
The Independent says the French incident - where a man - who is believed to have killed his boss - seemed to be trying to cause a mass explosion at a gas factory has inflamed public opinion.
John Lichfield for the paper in Paris says the details of the attack near Lyon seemed designed to play to suspicions that there is a "fifth column" of traitors within the country ready to attack it.
"France was just beginning to recover its breath after the January [Charlie Hebdo] killings," Lichfield writes.
The Independent also reports on the bomb in a Shia mosque in Kuwait which killed 27 worshippers.
The paper says Islamic state affiliated militants have claimed responsibility for the suicide bombing, saying it is an attack on a "temple of the rejectionists" - an IS term for Shia Muslims.
The Daily Express also reports a massacre in war-torn Syria.
The paper says IS fighters disguised as Kurdish militia went door to door in the town of Kobane shooting people.
As many as 150 people are thought to have died in what the paper says is the second largest mass killing the terror group has carried out.
It is not known if all the terror incidents yesterday are linked to the threat by an IS chief to make the month of Ramadan (which began last week) a time of "calamity" for non-Muslims.
However many newspapers believe there was a link, at least ideologically, between the various attacks - and ponder how safe the UK is.
The Daily Telegraph says Britain is on major alert on a weekend that sees London's massive gay Pride rally, and various events around the country to mark Armed Forces Day.
The threat to the UK from international terrorism continues to be assessed as severe, the paper reports.
The Daily Mail says that as police forces step up security at this weekend's events, officers have been given advice not to wear their uniforms once off duty and not to tell strangers what their job is.
Elsewhere in the paper, historian Michael Burleigh says "it's when, not if, the extremists hit Britain".
"These three related attacks - all significantly on the same day - are intended to show the global reach of Islamist fanatics. A reach that is increasing at a terrifying speed," he adds.
Columnist Jonathan Freedland in the Guardian says that we should not be afraid to brand these terror attacks "evil".
He suggests: "The butchers of Islamic State are following an age-old military tactic, one that would have been recognised by Genghis Khan and Attila the Hun: terrify the enemy."
The Sun says that it has helped foil a planned attack in the UK.
The paper says one of its undercover reporters was in touch with a British jihadist living in IS-controlled Syria.
It adds that the jihadist gave the reporter plans of how to make an explosive and details of an Armed Forces Day event in Merton, south-west London.
The Sun passed details of its exchange to anti-terrorism police.
In other news
With so much of the papers taken up with terror attacks, there is just time to summarise some of the other stories being carried in Saturday's press.
The Daily Mail says University College London will not reinstate Sir Tim Hunt to his honorary professorial post, after the Nobel Laureate scientist was caught up in a storm over supposedly sexist remarks he made during a speech.
The Mail says there have been growing support from fellow academics for the biochemist, who insists his remarks were clearly made in jest.
The Daily Telegraph says Boris Johnson is forming "an unholy alliance" with Theresa May and other senior Conservatives to oppose a third runway at Heathrow Airport.
The London Mayor has been a long-term opponent of the Heathrow plan, and he hopes to get Maidenhead MP Mrs May on board, as her constituency could be affected by any increased noise from the extra jets, the paper explains.
A report on where new airport capacity should go in the south-east is due out on Wednesday.
The Daily Mail claims an independent QC examining the claims of sexual abuse of children made against Labour peer Lord Janner will recommend the case is reopened by prosecutors.
The CPS decided not to prosecute the 86-year-old former MP because of his dementia, but the Mail says it understands a report from a senior barrister will force the decision to be reversed.
The CPS has not commented on the Mail story, but told the BBC that the review process is not complete.
The Daily Telegraph reports that Russia staged a military exercise where 33,000 of its troops rehearsed an invasion of Scandinavia.
The "dangerous game" took place in March, the paper adds.
The Daily Mail reports that police have recovered the Nanteos Cup - a wooden chalice reputed to be the original Holy Grail brought to England by Joseph of Arimathea.
The cup - stolen from a house in Herefordshire - was handed into West Mercia Police after a Crimewatch appeal, the paper notes.
Most experts believe it dates from the 14th century rather than biblical times, it adds.
And finally, neither the Daily Express nor most of the rest of Fleet Street can resist a picture story on Shabani, the "handsome" gorilla, who has attracted an army of female fans at the Japanese zoo where he lives.
The muscular 28-stone, 18-year-old, father-of-two has drawn many messages of admiration on Japanese social media sites.
A keeper at Higashiyama Zoo and Botanical Gardens tells the Express: "The Japanese are crazy... The Japanese love their fads.
"But I would say most people would consider him fairly dashing."
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