First 'milestone' Covid vaccine offers 90% protection
The developers - Pfizer and BioNTech - described it as a "great day for science and humanity", and say they plan to apply for emergency approval to use the vaccine by the end of the month. There are still huge challenges ahead, but the announcement has been warmly welcomed and the international stock markets have soared. Also: Azerbaijan's president rejects eye-witness accounts by BBC journalists of civilians being targeted in Nagorno-Karabakh.