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Overnight, the death toll rose to 20, most of the victims, students of Kerch Polytechnic. They were killed by their fellow student Vladislav Roslyakov. Investigators are trying to establish why. Just before midday yesterday, he’d walk into the college, armed with a gun and explosives, intent on committing massive murder. Media reports here picked the picture of a shy teenager with few friends in the college. He had recently obtained a license for a hunting weapon. The body of the 18-year-old attacker was discovered in the college library. It's thought he turned his gun on himself.

This is the world news from the BBC.

The first group of a wave of Hondurean migrants traveling towards the United States has arrived at the border of between Guatemala and Mexico. Some 3,000 people are making their way on the same route. They intend to travel north to Mexico's frontier with the US. President Trump has threatened to cut off millions of dollars in aid to countries in the region if they failed to stop the caravan.

The Trump administration is to withdraw from an international treaty that allows small packages to be sent to United States cheaply in a bid to put more pressure on China of what he deems unfair trade practices. The administration says it hurts the US postal services’ profits and stores’ prices. It asked that counterfeit goods are also shipped to the US under the Universal Postal Union’s terms.

The Australian State of Queensland has voted to decriminalize abortion which until now was illegal as an offense against morality. The new legislation will allow a fetus to be aborted until 22 weeks into the pregnancy. After that period, the approval of two doctors is needed.

Scientists have discovered that Antarctica is singing. Researchers studying the Ross Ice Shelf recorded the vibrations produced by the wind has whipped across the snow, and found that it sounded like eerie film music. Scientists believe the sounds could give them clues as to how the continent is handling climate change. Julian Chaput is a geophysicist from Colorado State University. The western Antarctica was losing the vast majority of ice, you know, decreasing in mass, and showing signs of strain, you know. The Ross Ice Shelf is not. It's actually very stable, which is in part why these singing events even occur at all. If an ice shelf had very unhealthy firn layers, or the melting firn layers, you may not be able to see these things. And so you know one flag for us is whether the ice shelves would stop singing in the near future over something we know is very rough.