Afghan security personel stand guard near the airport complex in Kandahar on Dec. 9. Taliban militants stormed the complex, triggering an all-night gun battle. (Jawed Tanveer/AFP/Getty Images)

Taliban militants killed more than 50 people at an airport in Afghanistan’s southern city of Kandahar late Tuesday and Wednesday during an audacious 20-hour assault, just as diplomatic efforts to revive peace talks between the Islamist insurgency and the Afghan government picked up momentum.

The attack began late Tuesday afternoon when a group of Taliban suicide bombers armed with rocket-propelled grenades, small arms and hand grenades broke through a main entrance of the airport, said Gen. Abdul Razaq Sherzai, the Afghan air force commander in Kandahar province.

For hours, Afghan forces at the combined military and civilian airport battled Taliban fighters who had taken family members of Afghan troops hostage in a residential area. The sprawling airport is also used by U.S. troops and is a hub of CIA operations, but there is no indication that any Americans were killed or injured in the fighting.

Late Wednesday, Afghan officials said at least 50 people, including women and children, had been killed along with all 14 attackers.

Afghan security personel stands guard after clashes between Taliban fighters and Afghan forces near the airport complex in Kandahar. (Allauddin Khan/AP)

The attack is seen as a show of the Taliban’s mobility and flexibility as key regional leaders attend a conference in Islamabad, Pakistan, called the Heart of Asia. Afghan, U.S., Pakistani and Chinese officials agreed during the meeting that they will immediately try to jump-start peace talks to end the 14-year Taliban insurgency.

A similar effort by the four countries collapsed this summer after it was revealed that the Taliban’s supreme leader, Mohammad Omar, had been dead for years. But officials expressed optimism Wednesday that the talks can eventually be revived.

“There is an affirmation of the need now to engage in this process or maybe, more accurately, reengage in it,” said U.S. Deputy Secretary of State Antony J. Blinken, who attended the conference in Islamabad.

Although most analysts think substantive talks could still be months away, Blinken said officials are hopeful that the Taliban is receiving the message that “it can’t achieve its goals militarily.”

And, Blinken added, “when everyone is rolling in the same direction, there is a greater chance of actually moving in that direction.”

After the conference, Afghan President Ashraf Ghani held an unscheduled meeting with Pakistan’s powerful army chief, Raheel Sharif.

“We are committed to work together with Afghanistan on the basis of mutual interest and respect,” Sharif said in a statement.

But on Wednesday, the Taliban proved they can still wreak havoc in Afghanistan. As Afghan troops struggled to defend Kandahar airport, they relied on help from American forces.

Coalition officials declined to discuss the specifics of their engagement in the clashes. The coalition said it has conducted “force protection measures to ensure all service members and civilians at the airport remained safe.”

It is the biggest strike by the militants since September, when they seized the northern city of Kunduz and held it for days. That was the largest city captured by the Taliban since the radical Islamist movement was driven from power in Kabul in November 2001 by Afghan opposition forces and U.S. airstrikes.

The attack comes amid reports of infighting among Taliban leaders. The Afghan government said last week that the Taliban’s new leader, Akhtar Mohammad Mansour, was wounded in internecine fighting in the Pakistani city of Quetta.

A Taliban spokesman denied the report.

In the past, the militants have launched attacks on at least two airports.

The most devastating assault was carried out in 2012 when Taliban combatants wearing U.S. military uniforms stormed Camp Bastion in neighboring Helmand province, destroying aircraft worth hundreds of millions of dollars.

Mohammad Sharif in Kabul and Tim Craig in Islamabad contributed to this report.

Read more:

Today's coverage from Post correspondents around the world