American troops have flown into the Afghan capital to help evacuate embassy personnel and other civilians in Kabul, a US official said on Saturday as quoted by Reuters. 

The Pentagon has said two battalions of Marines and one infantry battalion will arrive in Kabul by Sunday evening, involving about 3,000 troops, according to Reuters report.

“They have arrived, their arrival will continue 'til tomorrow,” the US official said as quoted by Reuters.

An infantry brigade combat team will also move out of Fort Bragg, North Carolina, to Kuwait to act as a quick reaction force for security in Kabul if needed, the Pentagon has said.

Britain and Canada are also sending troops as resistance from Afghan government forces crumbles and fears grow that an assault on Kabul could be just days away.

“These forces are being deployed to support the orderly and safe reduction of civilian personnel at the request of the State Department,” Pentagon spokesman John Kirby said on Friday, as well as to accelerate the processing of applications for Special Immigrant Visas for Afghan translators and interpreters.

“We expect to drawdown to a core diplomatic presence in Afghanistan in the coming weeks,” Kirby said, adding that the United States will continue to engage in diplomacy with the Afghan government and people.

Officials say a possible evacuation would involve the forceful use of US military force to protect people as they’re taken to Hamid Karzai International Airport where military transport planes would be waiting.