About 15,000 troops have launched a major offensive against Taliban insurgents in the Afghan town of Marjah.

US, British and Afghan soldiers are taking part in the biggest offensive against the Taliban since 2001. Marjah is regarded as the last Taliban stronghold in the southern Helmand province which is known for its opium production.

Eighty thousand people live in the city, which is thought to be harbouring 400 to a thousand Taliban fighters. Residents have been warned through pamphlets and radio not to take Taliban in. Hundreds of families have already fled the city.

The Marjah offensive was announced by NATO at the beginning of the month. It is the first large military operation since US president Barack Obama announced the deployment of 30,000 extra troops in December.