explosion reported in Khost province
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Suspected Taliban insurgents set off a car bomb at a US-operated base in Afghanistan, according to officials. It occurred shortly after US Defense Secretary James Mattis arrived in the country.

The attackers detonated the car bomb at an entrance to Camp Chapman, a secretive facility manned by US forces and private military contractors, said Mubarez Mohammad Zadran, a spokesman for the provincial governor, as cited by Reuters.

Photos on social media showed a plume of smoke rising from the scene of the attack in the eastern province of Khost.

"I am aware of a car bomb attack at one of the gates in the US base, but we are not allowed there to get more details," Zadran said.

Afghanistan map
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The attack was also confirmed by William Salvin, a spokesman for the US military in Afghanistan.

He said there appeared to be a number of Afghan casualties, but none among US or coalition personnel.

The attack occurred after Mattis' arrival to discuss the situation on the ground, as President Donald Trump contemplates sending more troops to Afghanistan.

General John Nicholson, the top American commander in Kabul, recently told Congress that he needs a few thousand more soldiers deployed to assist Afghan security forces, so they can eventually tackle the Taliban insurgency on their own.

The US currently has around 9,800 troops in Afghanistan. Although Washington ended its combat mission against the Taliban in 2014, troops are currently involved in backing up Afghan forces on the ground.

More than 100 Afghan soldiers were killed and injured in a Taliban attack on a military base in northern Afghanistan on Friday, according to the country's Defense Ministry.

The attack prompted Afghanistan's defense minister and chief of staff to resign on Monday.