Newspaper headlines: Trump 'for White House', Syrian child refugees and embryo research debate
As voters go to the polls across the UK, the BBC and other broadcasters are restricted to reporting only factual accounts of the events, in line with election day rules.
However, another election story also captures plenty of headlines. After John Kasich and Ted Cruz dropped out of the race for the Republican nomination for US president, Donald Trump is, in the words of the Times, "the only candidate left standing".
The businessman is widely expected to face Hillary Clinton in the battle for the White House, and says Times Washington bureau chief Rhys Blakely, "America is bracing itself for what promises to be the ugliest presidential election in generations".
Writing in the i, Andrew Buncombe says: "Cruz's determination to campaign as a religious and social conservative and a non-establishment candidate, was insufficient to overcome the whirlwind of support and momentum that Trump gathered around him".
Mr Trump, reports the Financial Times, heads towards November's election following a primary campaign in which a deep anti-establishment mood helped him turn from rank outsider to triumphant victor.
It says "analysts are split on whether the former host of The Apprentice reality TV show, who has spent as much time lambasting his party as he has hitting Mrs Clinton, can now rally a Republican establishment that has long believed that he was anathema to its values".
"Mrs Clinton has weaknesses as well as her many strengths, and this contest has barely even begun. But it is a plain fact that there is only one way to stop Mr Trump now, and that is by electing his opponent."
For the Daily Telegraph, Mr Trump's success represents as much a setback for the Republican Party's fortunes as it does for the candidates he defeated.
"It now needs to pull together or risk seeing another Democrat in the White House," the Telegraph says.
The Daily Telegraph and Daily Mail join several papers in focusing on David Cameron's refusal to apologise after calling Mr Trump "stupid and wrong" for proposing Muslims should be barred from the US as a way to address security concerns.
But they note Downing Street's indication that it would now "reach out" to the tycoon.
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- The pills that remember if you have taken them: A US company develops a tiny device the size of a grain of sand that sends out a signal when ingested - Times
- That's awkward! Joan Collins and Susanna Reid clash in near-identical dresses: The moment the actress and the TV presenter appeared on ITV's Good Morning Britain in similar-looking floral frocks is pictured in several papers including the Daily Express
- £50m diamond that's the size of a tennis ball: The Lesedi la Rona gem uncovered in Botswana last year is set to sell for a record sum at a London auction - Daily Mail
A government pledge to admit more unaccompanied Syrian refugee children from Europe into the UK sparks much debate.
The New Day says the decision provides a "lifeline" to desperate children who have fled the civil war.
The Daily Mirror welcomes the government decision. But the paper warns it would be a "big mistake" if just a "few handfuls" are allowed to settle.
The Daily Mail says it is "proud of this country's noble history of giving safe haven to those fleeing war and oppression" and the UK has a "moral duty" to help.
"There are times when cold logic gives way to a more visceral human response," it adds.
For the Guardian the announcement was a "welcome and long-overdue concession" even if it "regrettably... does not signal anything like a rethink of refugee policy".
The Sun says it recognises there is a case for taking in some children living in squalid camps in Europe. However, it says the existing policy of helping people living near the war zone itself remains the right focus.
While the pressure to take in children from camps across Europe is understandable, the government's commitment should be "temporary and limited", agrees the Times.
It is a breakthrough, says the Sun, which was hailed by scientists and blasted by critics.
Researchers in the UK and US have broken the record for growing human embryos in the lab, keeping them active beyond the stage when they would naturally implant in a mother's womb.
The Times says the development not only increases the potential for new IVF techniques and ways to prevent miscarriage but "pushed the boundaries of what is legally and ethically possible".
The work by teams from Cambridge University and Rockefeller University in New York was deliberately ended at the 13-day stage. But the Guardian reports it puts scientists into direct conflict with rules enshrined in law in at least a dozen countries that prohibit donated embryos from being grown in the lab for more than 14 days.
"While extending the allowed period for embryo research would be welcomed by some scientists, the move would be resisted by many, including religious groups already opposed to embryo research," says the paper.
According to the Financial Times, ethical debate over research into human embryos and stem cells has been fuelled by the rise of technology that allows modification of genes to tackle disease, although critics fear it could open the door to designer babies.
In the Daily Telegraph, Professor Robert Lovell-Badge from the London-based biomedical research centre the Francis Crick Institute says: "Proposing to extend the 14-day limit might be opening a can of worms, but would it lead to Pandora's box, or a treasure chest of valuable information?"
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