Nvidia shares sink as Chinese AI app spooks markets

US authorities say no survivors are expected after a military helicopter hit a passenger jet in Washington. Also: An Israeli soldier is among eight hostages freed from captivity in Gaza, and is F1 returning to Africa?

President Trump's nominee for health secretary, Robert F Kennedy Jr, has faced tough questioning at his first confirmation hearing in the US Senate. Also: scientists say asteroid Bennu contains building blocks of life.

At least 30 people killed in a crush at the Kumbh Mela in India, the world's biggest religious gathering. Also: Congo shuns peace talks, Mexico braces for mass return of migrants, and the rise of "grief apps".

A US judge has paused the enforcement of a sweeping White House order freezing federal grants and loans. Also: Israel says Netanyahu invited to meet Trump at White House next week, and should we all sleep like a caveman?

Our BBC North America correspondents answer your questions about President Donald Trump's first week in office, and his future plans for the United States.

Jordanian helicopters begin flying in aid to Gaza. Also: UN says hospitals in Goma in eastern Congo are struggling to cope after advance by M23 rebels, and 40 years on the computer game Tetris is still going strong.

The US chipmaker Nvidia has suffered the biggest single-day loss in US market history, as investors respond to the development of a low-cost AI chatbot by a Chinese company. Also: the diplomacy of renaming a submarine.

Palestinians displaced during the conflict are on the move as the ceasefire holds. Also; survivors gather at the Auschwitz concentration camp to mark 80 years since liberation, and why Paul McCartney thinks new musicians are missing out.

UN Secretary General António Guterres has called on Rwanda to withdraw its forces from DR Congo's territory and on the M23 rebel group to stop advancing on Goma. Also: how a random text message ended happily ever after.

For centuries, people have pursued the dream of eternal youth. Researchers have been making progress in understanding what happens in our bodies as we age. We may soon be able to use drugs to slow or even reverse ageing.