World News from the BBC

The Turkish authorities say Kurdish rebels have killed at least 13 soldiers in an ambush in the southeastern province of Diyarbakir. Seven others were wounded; two of them are in a critical condition. The attack, which happened

in broad day light

, is the first since the Kurdistan Workers' Party, the PKK, ended a ceasefire in February.

The United Nations General Assembly has voted to admit newly independent South Sudan as its 193rd member. From the UN in New York, Barbara Plett.

It was a breezy, sunny day in midtown Manhattan, and the wind caught the South Sudan flag as it unfurled in front of the United Nations. The flagpole was borrowed from Mauritius for the ceremony, but that didn't

detract

from the significance of the event or the enthusiasm of the Secretary General Ban Ki-moon.

"The United Nations is very pleased to welcome our 193rd member state - the newest nation in Africa, the newest nation on Earth."

The flag has six colours, including white for peace but also red for suffering, marking the millions of dead and displaced during decades of civil war with the north.

The United States has

set out

a new strategy for defending its military computer networks from attacks by hackers, saying it will in future treat the Internet as an operational domain in which to fight them. General James Cartwright told reporters that the focus was still on defence but offensive approaches were also needed.