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Many dead as earthquake hits Mexico

A 7.1 magnitude earthquake has hit Mexico, killing more than 200 people and destroying buildings in the capital, Mexico City. At least 21 children are among the dead, after a school collapsed.

The epicentre of the earthquake - which follows another measuring 8.1 earlier this month that left 91 dead - was near Atencingo in Puebla state, about 120km (75 miles) from Mexico City. Phone lines are down in the capital and about two million people there are without electricity. Residents have been warned not to smoke on the streets as gas mains may have been ruptured.

"We may still find people under the rubble," said President Peña Nieto in a televised address. "Stay in touch. Follow lines of communication. We will keep people updated."

Image copyright AFP

The earthquake "sent thousands of people into the streets, trembling, shaking, crying, and trying to reach their loved ones by phone", said the BBC's Juan Paullier, in Mexico City. "As time passes it is becoming clear that there are going to be many victims. In the capital alone, about 30 buildings collapsed."

Follow the latest developments on our live page.

Tech firms must fight terror, May to tell UN

Theresa May will use her speech to the United Nations General Assembly later to warn technology firms they must do more to stop the spread of extremist content. The prime minister will say they have to go "further and faster" in developing artificial intelligence so that terror propaganda comes offline sooner. Meanwhile, there's been reaction to US President Donald Trump's address to the UN on Tuesday. Iran, cited as one of a "small group of rogue regimes", described it as an "ignorant hate speech". North Korea, which Mr Trump said the US would "totally destroy" if necessary, has not yet issued a comment.

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Hurricane Maria heads for Puerto Rico and Virgin Islands

It's already caused widespread damage on Dominica. Now Hurricane Maria is heading for the Virgin Islands and Puerto Rico, as it makes its way through the Caribbean. It weakened briefly but has been classified once more as a maximum-strength, category 5 storm. Officials in Puerto Rico warn that debris left by Hurricane Irma earlier this month could add to the danger, with Maria creating sustained wind speeds of 175mph (280km/h). "You have to evacuate. Otherwise, you're going to die," Puerto Rico's public safety commissioner, Hector Pesquera, told the public. "I don't know how to make this any clearer."

Media playback is unsupported on your device Media caption What's in store for Wednesday?

What can we learn from Russia's latest military exercise?

These exercises come at an interesting moment. The Russian military is transitioning from the old Cold War-style Red Army into a more modern and flexible force, capable of conducting combined operations across land, sea and air, tailored to a variety of potential scenarios - just like the more sophisticated of Nato armies.

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What the papers say

There's continued focus on cabinet disagreements over Brexit, with the Times and the Daily Telegraph reporting that Foreign Secretary Boris Johnson has pulled back from the possibility of resignation after reaching a deal with Theresa May and her team. Meanwhile, Donald Trump's debut speech to the UN "stunned" those present, according to the Guardian, with its threat to "destroy" North Korea. And the Sun headlines on 47-year-old Tess Morten, who has amazed the medical world by having her first baby seven years after going through the menopause.

Daily digest

Lung cancer Life-extending drug approved for NHS in England

Tube attack Third man, aged 25, arrested

'Hacking risk' Greater Manchester Police still using Windows XP

'Sexism' outcry Dutch woman fined for urinating in public

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Today's lookahead

12:00 UK Cyclist Chris Froome follows his Tour de France and Vuelta victories by attempting to win the men's time trial at the Road World Championships in Bergen, Norway.

12:00 Prime Minister's Questions takes place, with First Secretary of State Damian Green deputising for Theresa May, who will address the UN General Assembly in New York later.

On this day

1970 The Soviet space probe Luna 16 lands on the Moon, becoming the first unmanned craft to collect samples from its surface.

From elsewhere

Inside the shadowy world of revenge hackers (Daily Beast)

Here's how to cut down on what you eat (Daily Telegraph)

Why we still love the 'cosy crime' of Agatha Christie (Independent)

The eternal seductive beauty of feathers (New Yorker)