DUSHANBE, September 30, 2015, Asia-Plus - The Taliban have overrun the northern Afghan city of Kunduz, taking control of most areas and freeing hundreds of prisoners from its jail.

Kunduz would be the first provincial capital taken by the Taliban since they lost power in 2001''s US-led invasion.

The attack came a day before the first anniversary of President Ashraf Ghani''s unity government.

Kunduz is strategically important as it acts as a transport hub for the north of the country.

It also has symbolic significance for the Taliban as it was their former northern stronghold before their government was overthrown, the BBC reports.

This attack is reportedly one of the most serious security breaches since the start of the Taliban insurgency 14 years ago.  But the Taliban''s main challenge will now be to hold the city, experts say.

Kunduz has a huge strategic significance as it is considered a gateway to Afghanistan''s northern provinces and shares a border with Tajikistan, Afghanistan''s Central Asian neighbor.

The Taliban already control huge chunks of the province''s rural areas, where the majority of the population live. The insurgents have intensified their fighting in the province over the past two years.

According to the BBC , they are the dominant militant group in the province, with an estimated 2,000 fighters. But there are also reportedly hundreds of foreign fighters associated with al-Qaeda, so-called Islamic State and the Islamic Movement of Uzbekistan (IMU).

Kunduz province has seen a number of attacks since April, with the Taliban joining forces with other insurgents.

Militant violence has increased across Afghanistan since the departure of most US and NATO forces last year.

Reuters reports that U.S. and Afghan officials have this year sought to portray the Taliban as unable to take and hold major territory and weakened by confirmation of the death of the movement''s founder, Mullah Mohammad Omar.

The swift and well-planned assault on Kunduz, a city of 300,000, was intended to show the Taliban''s new leader, Mullah Akhtar Mansour, is able to win in battle, Taliban spokesman Zabihullah Mujahid was quoted as saying.

“I have no doubt the Afghan forces will retake Kunduz eventually, but the damage to the reputation of Afghan forces is already done,” Omar Hamid, head of Asia analysis for IHS Country Risk security analysts, told Reuters in an interview.