First Thing: the Obamas endorse Kamala Harris for president

The US vice president has now won the backing of all the Democratic party’s high-profile figures. Plus: a sweltering summer in Las Vegas

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Good morning.

The former president Barack Obama and his wife Michelle, the former first lady, have officially endorsed Kamala Harris as the Democratic nominee for US president in a video released by her campaign on Friday. “We called to say Michelle and I couldn’t be prouder to endorse you and do everything we can to get you through this election and into the Oval Office,” Barack Obama said in the video.

“This is going to be historic,” Michelle Obama said.

The Obamas’ endorsement means that the vice-president has now won the backing of all the party’s politically active high-profile figures for her White House bid.

• Who else has endorsed Harris? Bill and Hillary Clinton, Nancy Pelosi, a host of state governors and the most senior Democrats in Congress – as well as Joe Biden himself, after ending his re-election campaign – have all endorsed Harris.

• What do the polls say? While Harris is closing the gap on Donald Trump, she is still narrowly trailing in the swing states of Michigan, Pennsylvania, Arizona and Georgia.

• How did Harris’s meeting with Benjamin Netanyahu go on Thursday? In comments that were closely watched for signs of a shift from Biden’s policy approach, Harris asserted that while “Israel has a right to defend itself”, how Israel defended itself mattered: “We cannot look away in the face of these tragedies [in Gaza]. We cannot allow ourselves to become numb to the suffering and I will not be silent.”

• How important is Harris’s Israel policy to her presidential bid? More than 700,000 Americans voted “uncommitted”, or its equivalent, in state primaries as a message to Biden that he risked losing significant support in November if he did not shift away from his support for Israel. “[Harris] could get my vote, but it’s going to be a difficult journey. We actually need to see action,” said Fadel Nabilsi, a Palestinian American attorney who voted uncommitted in Michigan’s Democratic primary.

France’s high-speed rail network struck by arson attacks before Olympics opening ceremony

Coordinated “malicious acts” – including arson attacks – on France’s high-speed rail network have brought major disruption to many of the country’s busiest rail lines just hours before the opening ceremony of the Olympics in Paris. No one yet has claimed responsibility for the attacks.

• What happened? Arsonists targeted installations along the lines connecting Paris with the country’s west, north and east, cutting and burning crucial cable lines.

• How many people will be affected? Authorities estimate that the travel plans of about 800,000 French holidaymakers will be disrupted this weekend because of the attacks.

In other news …

• The US justice department has arrested two leaders of Mexico’s powerful Sinaloa cartel – Ismael Zambada García, known as “El Mayo”, one of the group’s co-founders, and Joaquín Guzmán López – for their alleged roles in leading deadly fentanyl manufacturing and trafficking networks.

• Christopher Wray, the FBI director, is raising questions about whether Donald Trump was actually shot by a bullet during an assassination attempt earlier this month, or if he had instead been struck by shrapnel.

• A California man was arrested on Thursday and accused of starting the Park fire, the state’s largest wildfire, by pushing a burning car into a gully.

• A new inspector general’s report released on Thursday has determined that the former attorney general Bill Barr was personally involved in a decision to release an unusual and misleading justice department statement on the eve of the 2020 election suggesting there may have been voter fraud in Pennsylvania.

Stat of the day: An estimated 123,000 people are living outside on the streets of California in tents, trailers, cars and makeshift shelters

With more than 180,000 people experiencing homelessness in California – an estimated 123,000 living rough on the streets in tents, trailers, cars and makeshift shelters – the California governor, Gavin Newsom, issued an executive order on Thursday calling for the removal of homeless encampments across the state. The order, which calls for shutdowns of encampments on state property and urges local governments to follow suit, cites a controversial US supreme court decision in June saying that unhoused people sleeping outside can be ticketed and jailed even when there is no shelter available.

“The folks the governor is referring to are in really desperate situations,” said Jennifer Friedenbach, the executive director of the Coalition on Homelessness in San Francisco. “They’re trying to stay out of the way. They’re living near freeways where it’s really noisy, the air quality is bad and the conditions are horrible, because they have no other choice. Arresting them is not going to change that.”

Don’t miss this: the Gaza City orphanage director trying to survive with the children in his care

Hazem Rahma runs an orphanage in Gaza City with his wife, looking after children, many of whom are disabled and require extra medical attention. After Israeli forces bombed a mosque next door, blowing out the orphanage’s windows and damaging the playroom and kitchen, Rahma and his wife relied on strangers to help them carry the children down the evacuation road to Khan Younis, where another airstrike injured some of his party, and eventually to al-Mawasi.

“There is no safe place in the Gaza Strip,” Rahma said in an interview with the Guardian. “The Israeli army declared al-Mawasi a safe area, but it has been attacked more than once; there have been several deadly attacks in the past few days. Fear fills our hearts. We are afraid everywhere: while we are in the tent, if we go out to get anything. We could be bombed at any time.”

… or this: a sweltering summer in Las Vegas

Record heat is killing hundreds in Nevada’s Clark county, home of Las Vegas and 2.3 million people. June was Las Vegas’s hottest on record, while in July, the city experienced a record seven days at 115F or higher and set a new all-time high of 120F. But the region is among the fastest-growing metro areas in the US, and keeps getting bigger. In the last 50 years, roughly 2 million people have moved here, with nearly a million more expected by 2060.

Climate check: the link between childhood air pollution and adult lung health

Researchers at the University of Southern California have found that air pollution breathed in during childhood is one of the contributing factors for adult lung health. The study, which began in 1992 with children who are now in their 40s, found that people with higher childhood exposures to particle pollution and nitrogen dioxide had a higher likelihood of bronchitic symptoms as an adult. While this relationship was strongest for those who had developed asthma and lung problems as children, a relationship also existed between childhood air pollution and adult bronchitic symptoms for people who did not have lung problems as children.

Last Thing: A gallery tour designed for people with dementia

The staff at Kunstmuseum Den Haag in The Hague have designed a gallery tour specifically for people with dementia and their carers. The tour is steeped in colours and smells, with colouring-in sheets, a carpet of lavender and palettes to engage attenders taking in artwork like Paul Signac’s pointillist Cassis, Cap Lombard, Opus 196 and Alexej von Jawlensky’s expressionist Head of a Woman. “The heart does not get dementia,” said Maaike Staffhorst, the museum’s spokesperson. “People with dementia still have feelings and they can give a sense of fulfilment.”

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