The Pakistani Taliban on Monday threatened more attacks after claiming responsibility for a brazen five-hour assault on the country’s busiest airport in which gunmen disguised as police guards stormed the international airport in Karachi, set off explosions and killed 18 people.

The claim further diminished prospects for a resumption of peace talks with the Pakistani Taliban that officials had hoped could bring an end to the group’s bloody, years-long campaign seeking to overthrow the country’s U.S.-allied government. The insurgency has shaken the stability of the nuclear-armed country, which borders Afghanistan, where international forces have been fighting the Afghan Taliban for more than a decade.

Peace talks floundered in recent weeks, and the Taliban called off a cease-fire they had declared during the negotiations. Since then, Pakistani troops have hit the group’s hideouts with airstrikes in the country’s troubled northwestern region, killing dozens of suspected militants. Residents claim several civilians were also killed in the strikes.

The Taliban said the assault on the Jinnah International Airport in Karachi, Pakistan’s largest city and the country’s economic heart, was in revenge for the killing last November of the militant group’s leader in a U.S. drone strike

In a telephone call to The Associated Press, the group’s spokesman, Shahidullah Shahid, warned that “such attacks will continue until there is a permanent ceasefire.”

The attack began late Sunday when 10 gunmen, at least some disguised as policemen, stormed into a section of the sprawling airport where a terminal for VIP flights and cargo is located. They opened fire with machine guns and rocket launchers, sparking a battle with security forces that lasted until around dawn.

Heavy gunfire and multiple explosions were heard coming from the terminal amid the fighting. A major fire rose from the airport, illuminating the night sky in an orange glow as the silhouettes of jets could be seen. As dawn broke Monday, smoke could still be seen billowing in the air.

At least some of the gunmen wore the uniform of the Airport Security Force, said an official at the scene near the terminal. All the attackers wore explosives vests, some of which were detonated when they were shot at by the police, the official said, speaking on condition of anonymity because he was not authorized to talk to the media.

A cargo building was left completely gutted by the fire and the explosions, said Rizwan Akhtar, the chief of Pakistan’s elite paramilitary Rangers.

Just before dawn, security forces regained control of the airport, and all 10 attackers were dead, Akhtar said. He said some of the attackers appeared to be Uzbeks but officials were still investigating to determine their identity and nationality.

At least 18 people were killed besides the attackers, mostly airport security or other airport personnel, according to Seemi Jamali from Karachi’s Jinnah Hospital.

During the battle, airport operations were suspended and all incoming flights were diverted. An Emirates flight in Karachi bound for Dubai had to be cancelled and passengers were escorted off the plane because of the fighting, the Dubai-based carrier said.

Late Monday afternoon, the airport reopened and was fully functioning, according to Shujaat Azeem, the prime minister’s adviser for civil aviation.

Shahid, the spokesman for Tehrik-e-Taliban Pakistan — as the Pakistani Taliban are known — said the attack was to avenge the killing of Hakimullah Mehsud, the Taliban chief who died in an American drone strike last November.

Mehsud’s death was the last major killing of a militant commander under the controversial drone program.

The CIA, as reported by The Associated Press in May, has largely wound down its drone program over Pakistan, and there hasn’t been a drone strike in Pakistan since Christmas.

Shahid said the attack on the Karachi airport had been planned out before the peace talks started and was put on hold during the negotiations.

Security officials in Karachi had feared that if the peace talks broke down, their city would be a likely spot for militant retribution.

The Pakistani Taliban and their allies increasingly are gaining a foothold in Karachi, the country’s largest city and the site of frequent militant attacks in the past. It is the country’s economic hub and any militant activity targeting its airport would likely strike a heavy blow to foreign investment in the country.

In May 2011, militants waged an 18-hour siege at a naval base in Karachi, killing 10 people in an assault that deeply embarrassed the armed forces.

Meanwhile, the death toll from another deadly attack Sunday night rose to 24 in the Baluchistan town of Tuftan near the Iranian border. Militants attacked a group of Shiite Muslim religious pilgrims staying at a hotel after they returned to Pakistan. Government official Ghulam Mustafa said that the bodies have been sent by helicopter to the provincial capital of Quetta.

There was no claim of responsibility for that incident, but Sunni Muslim extremists have often targeted Shiites because they don’t consider them to be true Muslims.

(AP)