Monday’s top story: US deploys aircraft carrier and bombers to Middle East amid ‘escalatory indications’ from Tehran. Plus, do the European elections matter?

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

Bolton warns of ‘unrelenting force’ if Iran attacks US or allies

The US national security adviser, John Bolton, has raised Middle East tensions by announcing that an aircraft carrier and a bomber task force are being sent to the region in response to “escalatory indications and warnings” from Iran. It is unclear exactly what “indications” Bolton was referring to in his statement on Sunday, and the Abraham Lincoln carrier strike group’s voyage to the Gulf was previously planned. But Bolton said the military escalation was meant as a message to Tehran “that any attack on United States interests or on those of our allies will be met with unrelenting force”.

Gaza violence. Donald Trump tweeted his “100%” support for Israel after at least 19 Palestinians and four Israelis were killed over the weekend, amid some of the worst fighting in and around Gaza in recent years.

Cancer Town, USA: the brutal history of Reserve, Louisiana

Play Video 7:57 'People are dying horrible deaths': the Louisiana town where cancer haunts the streets – video

Louisiana’s “Cancer Alley” has the worst air in the US, and residents of the town of Reserve face a cancer risk 50 times greater than the average American. In the first of a series of special reports over the coming year, Jamiles Lartey and Oliver Laughland meet the people from the predominantly black community who are battling for cleaner air, while living with the legacy of a toxic chemical plant and the long shadow of slavery.

‘Horrible deaths’. Reserve locals feel neglected by their elected representatives, by industry, and by the national media, as they tell Guardian reporters in our film, Cancer Town, USA.

Mueller ‘agrees tentative date’ to testify before Congress

Facebook Twitter Pinterest Robert Mueller. The Democratic congressman David Cicilline said Mueller might testify as soon as 15 May. Photograph: Tasos Katopodis/Getty Images

The Democratic congressman David Cicilline has said the House judiciary committee hopes to interview Robert Mueller about his Trump-Russia investigation on 15 May, though Cicilline walked back some of his previous comments on Sunday, in which he had claimed a representative for the special counsel had accepted the committee’s invitation and set the tentative date for his testimony.

Trump tweets. Trump tweeted on Sunday that “Bob Mueller should not testify”, suggesting Democrats were “looking for a redo” because they were dissatisfied by the conclusions of the Mueller report.

Former Nxivm members to testify against cult leader

Facebook Twitter Pinterest The former Smallville star Allison Mack pleaded guilty to racketeering charges over her involvement with Nxivm and its leader, Keith Raniere. Photograph: Mark Lennihan/AP

Several former members of the controversial self-help group Nxivm (pronounced “Nexium”) are expected to break their previous vow of silence to testify against its spiritual leader, Keith Raniere, over allegations that the 58-year-old kept women as virtual sex slaves and threatened to release “collateral” material such as nude photos if they resisted. Opening arguments in Raniere’s sex-trafficking trial are set for Tuesday at a federal court in Brooklyn.

Smallville star. There is speculation that the prosecution’s witness list could include the actor Allison Mack, who has admitted collecting “collateral” against women for Raniere, and who fled to Mexico with him before his arrest there last year.

Crib sheet

Must-reads

Facebook Twitter Pinterest Florence Fang, the owner of the Flintstones House in Hillsborough, California, at her controversial property. Photograph: Cayce Clifford/The Guardian

At home with the embattled owner of the ‘Flintstone House’

The retired media magnate Florence Fang decorated the landscape around her colourful Bay Area home with dinosaurs, aliens and other outlandish items. Now the town of Hillsborough, California, is suing her, claiming the property is a “public nuisance”. Julia Carrie Wong paid a visit to the “Flintstone House”.

NRA’s troubles could dent Trump’s 2020 bid

The NRA spent tens of millions to help Trump win in 2016, but the group’s recent financial losses and allegations of financial impropriety may render it unable to do the same in 2020. The president’s tweets suggest he’s worried, as Peter Stone reports.

Do the European elections matter?

Europe is preparing to elect a new parliament in Brussels at one of the most volatile moments in its history, with populism on the rise and Brexit on the horizon. Jennifer Rankin explains where power resides in the EU, and whether the elections will make a difference.

Madhur Jaffrey on acting, food and race

Madhur Jaffrey has had two extraordinary careers, first as an actor and then as the cook credited with introducing Indian food to western kitchens. “The young Indian [food writers], they don’t take any guff from anybody. I’m so proud of them,” she tells Rebecca Flint Marx.

Opinion

Joe Biden has joined his rival Democratic 2020 hopefuls on the campaign trail in Iowa with what looks like a commanding lead in the polls. But nobody really knows which way the Hawkeye state’s caucuses will blow, says Art Cullen. That depends which candidate is really listening to its voters.

The talk is not so much of who is up or who is down, but who seems to genuinely understand what we’re up against.

Sport

The four-time Olympic sprinting champion Michael Johnson suffered a stroke eight months ago at age 50. To run again, he first had to learn to walk, he tells Denis Campbell. “The first day we covered about 200 metres – having been the world record-holder at that event, it wasn’t the most positive thing.”

Liverpool are back atop the Premier League table as the season enters its final week, after their thrilling 3-2 win at Newcastle. Manchester United’s slim hopes of Champions League qualification faded altogether with a disappointing 1-1 draw at Huddersfield. Those are two of 10 talking points from the weekend’s action.

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