No sign of Ukrainian surrender in Mariupol

The deadline issued by Russia for Ukrainian forces in Mariupol to lay down their weapons today has passed - with no sign that the defenders have surrendered. We get the latest from our correspondent. Meanwhile, efforts to try to evacuate civilians from the devastated city continue. We explain what is meant by “humanitarian corridor” and hear from people who have previously fled the city or have relatives there.

We hear reaction to the news that Russian and Belarusian players will not be allowed to compete at Wimbledon tennis tournament this year because of the invasion of Ukraine.

Scientists say that bacteria in urine could help them identify an aggressive form of prostate cancer. We learn about the significance of the discovery.

To mark the anniversary of the Columbine High School school shooting in 1999 in the United States - and the fact that mass shootings continue – a group of American teenagers have written plays about their own experiences of gun violence. We hear their stories.

(Photo: Residents walk along a street damaged during Ukraine-Russia conflict in the southern port city of Mariupol, Ukraine April 19, 2022. Credit: Alexander Ermochenko/Reuters)