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Good morning, I’m Tim Walker with today’s essential stories.

Sri Lanka authorities were warned of attacks

Officials in Sri Lanka were warned of the threat of attacks two weeks before the wave of Easter Sunday bombings in which at least 290 people were killed and 500 injured. A government spokesman admitted on Monday that authorities even had the names of suspects before the attacks, which targeted churches and luxury hotels in the capital, Colombo, and two other cities. Police have arrested 24 suspects. The Sri Lankan defence minister said the culprits were religious extremists, but no group has yet claimed responsibility. Here is what we know so far.

American victims. At least 30 foreigners, including “several” Americans, were among those killed. Survivors have given their accounts, including one family who believe they encountered a bomber outside St Sebastian’s church in Negombo.

Social media. The Sri Lankan government shut down social media to prevent the spread of misinformation in the aftermath of the bombings. The decision demonstrates a sense that social media’s benefits are outweighed by its dangers, write Julia Carrie Wong and Kari Paul.

Comedian wins landslide presidential election in Ukraine

Play Video 1:30 Ukraine election: Poroshenko concedes as exit polls show landslide victory for Zelenskiy – video

A 41-year-old comedian whose only experience of government is playing a president in a popular TV series has won a landslide victory in Ukraine’s presidential election. Volodymyr Zelenskiy won 73.4% of the vote in a runoff against the incumbent, Petro Poroshenko, who won just 24.4%. Like the fictional character he plays, Zelenskiy has promised to clean up the country’s corrupt politics, but he has offered little in the way of policy specifics.

North Macedonia. A presidential election in North Macedonia will go to a runoff after turnout proved too low for any candidate to win outright. The contest is seen as a chance for voters to weigh in on the country’s controversial name change, from Macedonia to North Macedonia, which took effect in February.

Bernie battles the Democratic establishment – again

Facebook Twitter Pinterest Bernie Sanders launches his 2020 campaign in Brooklyn last month. Photograph: Johannes Eisele/AFP/Getty Images

Just as in 2016, Bernie Sanders faces a simmering civil war with fellow Democrats, in which he rails against the party establishment, while they worry the poll frontrunner is too leftwing to defeat Donald Trump. As Lauren Gambino reports, the battle has spilled into the open with a spat between Sanders and a liberal thinktank, as well as a New York Times report revealing a series of private dinners in which Democratic leaders met to discuss “the matter of What To Do About Bernie”.

Mueller fallout. Democrats remain split on whether to impeach Trump over the findings of the Mueller report, while the president’s personal lawyer Rudy Giuliani claimed on Sunday: “There’s nothing wrong with taking information from Russians.”

Evidence of further graves at Florida reform school

Facebook Twitter Pinterest White metal crosses mark graves at the former Arthur G Dozier School for Boys in Marianna, Florida. Photograph: Michael Spooneybarger/Reuters

Another 27 “possible” graves have been found at the site of the former Arthur G Dozier School for Boys in Marianna, Florida, where evidence of human remains had already been uncovered in 55 such graves. Survivors of the notorious reform school, where brutal beatings, rapes and other forms of abuse were routine, say they have known for years that the 55 graves revealed by a 2016 study were not the end of the story, as Richard Luscombe reports.

Violent deaths. Researchers from the University of South Florida believe there are a minimum of 98 graves to be found at the school, which closed in 2011. Many of the human remains recovered show signs of gunshot wounds or blunt force trauma.

Crib sheet

Larry Mitchell Hopkins, a member of an armed militia arrested on Saturday after detaining migrants at the US-Mexico border , was arrested in 2006 on a similar charge – being a felon in possession of firearms – while impersonating a police officer.

The Electronic Frontier Foundation, a digital civil liberties group, has called on Facebook to tackle the proliferation of fake user profiles created by law enforcement agencies such as US Immigration and Customs Enforcement.

Morehouse College, the historically all-male black college in Atlanta, has said it will allow transgender men and “individuals who self-identify as men, regardless of the sex assigned to them at birth” to apply for admission beginning in 2020.

The bodies of three renowned mountaineers, including the American alpinist Jess Roskelley, have been found at Banff National Park in Canada after they went missing in an avalanche last week.

Must-reads

Facebook Twitter Pinterest Will Tony Stark make it home? Spoiler alert: yes. Photograph: AP

Addressing the Avengers: Endgame theories

With days to go until the climactic movie in the Marvel Cinematic Universe’s 21-film, 11-year series, fan theories are swirling around Avengers: Endgame. Will Steve Rogers retire, or expire? Who will kill Thanos, if anyone? Why did Hawkeye get that haircut? Clara Mae examines the possibilities.

In 2020, voting machines will leave a paper trail

For years, many Americans have voted on machines that leave behind no proof the votes counted match the votes cast. In 2020, many jurisdictions are introducing new machines designed to allay fears of Russian hacking. But the new technology isn’t foolproof either, as Jordan Wilkie reports.

Why a sceptic went to see a psychic

Rebecca Flint Marx consulted friends, her therapist and a rabbi about her troubled relationship before reluctantly turning to a psychic for advice. Frank, whose clients included John Lennon, left her reassured, “because he saw things that were true, but also because he saw hope where I couldn’t”.

A toxic mine threatens pristine Alaska

A Canadian company wants to dig a mile-wide, 600ft deep mine in Bristol Bay, Alaska, wiping out 3,500 acres of wetlands and 80-plus miles of salmon streams – and Trump’s EPA is all for it. Kim Heacox says it’s just one more example of greedy men exploiting nature for profit.

Opinion

Democrats differ on whether to tackle Trump at the ballot box, or to pursue impeachment. But Bhaskar Sunkara says Trumpism must be defeated by leftwing politics, not political theatre.

Trump is the legitimate president by rules of the game that liberals have largely accepted. The only way to repudiate his right-populism is at the ballot box, decisively showing what polls indicate — that Americans want real, progressive solutions to their problems.

Sport

The British boxer and two-time junior welterweight champion, Amir Khan, has insisted he’s “not one of them guys to quit”, after withdrawing from his challenge for Terence Crawford’s WBO welterweight title in the sixth round, when, he claims, a low blow to the groin left him incapacitated.

Iceland captain Gylfi Sigurdsson orchestrated Everton’s crushing 4-0 defeat of Manchester United at Goodison Park. Meanwhile, after vanquishing City in their Champions League clash last week, Spurs failed to repeat the feat on Saturday. Those are two of 10 talking points from the weekend’s Premier League action.

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