Nic Robertson

More recently the TTP has had high level defections to ISIS, the leaders taking their fighters with them, iSIS is focused on an Afghan fight, and the TTP have brought significant fire power with them to help ISIS grow. But in this region the Taliban is still dominant.

This is the biggest town they've been able to take since 2001, this is a significant target and prize for the Taliban.

Since about April this year, the Taliban increased their strength in the countryside to the north of Kunduz and have essentially had it in their sights since then.

The army by its retreat yesterday, and the police by their retreat as well, have really shown that there are question marks over the government's ability to impose its writ in Kunduz, at least in the short term.