President Ruto leads the tributes to Kenya's former prime minister and long-time opposition leader.
A new study looks at ancient exposure to the metal
Why less ice might mean more fire
The island’s unique plants are being preserved in the world’s biggest seed bank
A by-election in Wales reveals Labour’s vulnerability
Men with guns now run the country
BBC Verify investigates the damage done by two years of war, which could take $70bn and decades to repair.
Evidence of the intentional targeting of civilians in el-Fasher amounts to war crimes, researchers say.
Our podcast on science and technology. The spread of the highly potent drugs demands a fresh approach to drug policy
Shadi Abu Sido told the BBC an Israeli prison officer said his family had been killed.
CEO Sam Altman says upcoming versions of the popular chatbot would enable it to behave in a more human-like way - "but only if you want it".
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