A US air strike that destroyed a medical charity's clinic in northern Afghanistan, killing 42 people, was not a war crime, the Pentagon has said.

Medical charity Medecins Sans Frontieres says three of its staff are killed when its clinic in the Afghan city of Kunduz was hit by sustained bombing.

Fierce fighting is continuing between Afghan forces and the Taliban in parts of Afghanistan's northern city of Kunduz, despite government claims that it had regained control of the city.

A tablet device that can withstand being doused in chlorine is developed to help medics caring for patients with Ebola