In today’s newsletter: In April, fighting broke out between two rival factions – with no end in sight, the UN is investigating

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Last week the United Nations discovered a mass grave in Sudan’s West Darfur in which 87 people were buried, prompting the UN high commissioner for Human Rights to demand a “thorough and independent investigation” into activity in the region.

Ukraine | Explosions have reportedly hit the Kerch bridge connecting the Crimean peninsula to Russia, a heavily guarded road and rail link that is among the Kremlin’s most important infrastructure projects. The head of the Russian-controlled administration in Crimea, said traffic had been stopped because of “an emergency situation”. Two people have been killed and a child was injured.

Environment | Southern Europe is bracing for a second “heat storm” in a week. Record temperatures across the Mediterranean could be broken on Tuesday, and people in Italy have been told to prepare for most intense heatwave ‘of all time’. Meanwhile in the US more than 100 million people were under extreme heat advisories this weekend.

Iran | Iran’s “morality police” have returned to the streets 10 months after the death of a woman in their custody sparked nationwide protests. It comes as authorities announce a new campaign to force women to wear the Islamic headscarf.

Hospitals | The government is on track to break a key election promise from Boris Johnson to build 40 new hospitals in England by the end of the decade, a damning report by the public spending watchdog has found.

Music | France’s favourite “petite Anglaise”, the British-born singer and actor Jane Birkin, has died at her home in Paris aged 76. The French president, Emmanuel Macron, paid tribute to Birkin, saying she “embodied freedom and sang the most beautiful words in our language”.