Wednesday’s top story: Warren and Sanders take on the moderates in second round of 2020 debates. Plus, meet the man who’s swimming the Pacific garbage patch

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

Progressives emerge triumphant from fiery Detroit debate

It was pitched as a battle between Bernie Sanders and Elizabeth Warren for the leadership of the party’s left wing. Instead, the Democratic presidential debate in Detroit on Tuesday saw the two progressive senators team up to weather fierce attacks from moderate candidates such as Johns Hickenlooper and Delaney, who said Sanders’ signature Medicare for All policy represented “the creep toward socialism”. Warren responded that Democrats could not win back the White House with “small ideas and spinelessness”.

ACLU: 900 child separations since judge ordered curtailment

Facebook Twitter Pinterest A child at a protest against the treatment of children in immigration detention in Texas last month. Photograph: José Luis González/Reuters

The American Civil Liberties Union (ACLU) says more than 900 migrant children have been separated from their families at the US-Mexican border since last June, when a judge ordered US immigration authorities to sharply curtail the practice. In a Tuesday court filing, the group said 911 children had been split from their families at the border since the 2018 court order, and that one in five of them were under five years old.

‘Criminal conduct.’ The judge who issued the 2018 court order said family separation should halt except in limited circumstances, such as a parent’s criminal history. Of the 911 separated children, 678 had parents facing criminal allegations.

Pregnant detainees. Under Obama, immigration authorities had a policy of presumption of release for all pregnant women. But in the Trump era more and more pregnant migrants are facing prolonged detention, as Cady Voge reports.

Canada fugitives were let go after alcohol checkpoint stop

Facebook Twitter Pinterest Royal Canadian Mounted Police officers search the area around Gillam, Manitoba, for the two teenage murder suspects. Photograph: Rcmp Handout/EPA

The two teenagers accused of killing three people in remote northern Canada were stopped by authorities at an alcohol search checkpoint in Manitoba last week, but Split Lake First Nations safety officers let them go because the pair had not yet been named as suspects. It is a frustrating revelation amid the manhunt for Kam McLeod, 19, and Bryer Schmegelsky, 18, who are suspected of fatally shooting American Chynna Deese and her Australian boyfriend, Lucas Fowler, along with Leonard Dyck, a Canadian botanist.

Long getaway. The teenagers are believed to have driven 3,000km (1,800 miles) from British Columbia – where the victims were found dead – to Manitoba, where they crashed their Toyota RAV4 on a gravel road near the town of Gillam, set it alight and vanished.

Hong Kong protests continue after rioting charges

Play Video 0:49 Hong Kong police officer threatens protesters with shotgun – video

Several hundred people were involved in tense protests at two police stations in Hong Kong late on Tuesday, as 20 pro-democracy demonstrators appeared in court charged with rioting amid the continuing political crisis in the former British colony. The 20 had been arrested on Sunday during another round of violent clashes with police. The rare charge of rioting can lead to a prison sentence of up to 10 years.

Chinese influence. The Trump administration reports a buildup of Chinese forces on the Hong Kong border, while westerners living in Hong Kong are being targeted online by Chinese state media and local lawmakers accusing them of stoking the unrest.

Crib sheet

Must-reads

Facebook Twitter Pinterest Ben Lecomte with a discarded toothbrush he found while swimming in the Pacific. Photograph: @osleston (1)

Why Ben Lecomte is paddling in plastic

The 52-year-old long-distance swimmer Ben Lecomte is freestyling through the Great Pacific Garbage Patch from Hawaii to San Francisco, to better understand how plastic is affecting our oceans. There is no “trash island”, the Frenchman tells Esha Chhabra, but rather an “underwater smog of microplastic”.

The Honduran community that’s sinking underwater

The Guardian’s Running Dry series is exploring how climate change has affected Central America, destroying communities and driving northerly migration. Today, Nina Lakhani reports from Choluteca in Honduras, where coastal towns will soon be wiped out by rising sea levels.

Petula Clark: ‘Elvis angled for a threesome’

One of the bestselling British female artists of all time, Petula Clark broke America with her 1964 hit Downtown. As she prepares to return to the stage at 86, Clark tells Elle Hunt about stoking controversy with with Harry Belafonte, her friendship with Karen Carpenter – and a dressing room encounter with the King.

Tell us who is transforming your city

The Guardian is launching a project to find the people and organisations who are transforming cities across the US for the better. We’re starting with Cleveland – and we need your help. Tell us here about the ordinary people you know who are making a difference.

Opinion

The term “climate change” was spread by a Republican administration, eager to downplay an existential threat. Unless we start referring to global heating as the crisis it is, few will heed the warnings, say academics from Columbia University’s national center for disaster preparedness.

There is no longer any doubt that climate change is an unprecedented planetary emergency. And the terms we use to describe this crisis must deliberately reflect an appropriate sense of urgency.

Sport

The US women’s soccer coach, Jill Ellis, has announced she will step down, weeks after winning her second consecutive World Cup title. Meanwhile the USWNT is heading towards mediation with US Soccer in its fight over equal pay, but Beau Dure says both sides are muddying the waters with fuzzy numbers.

A 16-year-old boy from Pennsylvania has won the Fortnite World Cup after the biggest video game competition of all time. Its size and success raise a pressing question, says Bryan Armen Graham: not whether esports is the future of sports entertainment, but whether there’s any possible scenario where it’s not.

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