Afghan commando opens fire on USA troops, kills 3, wounds 1

Two U.S. soldiers were killed in eastern Nangarhar province in Afghanistan, an official of the provincial government said on Saturday.

A U.S. official said that the soldiers were shot by an Afghan commando in what is being called an "insider attack" because the shooter belonged to a military force that is considered an ally of the U.S. Army in the country.

In a statement, US Forces Afghanistan said members of the Afghan Border Police in Helmand Province were killed and wounded during an operation involving US and Afghan defense and security forces.

North Atlantic Treaty Organisation forces in Kabul declined to immediately comment on the killings. The wounded soldier has been evacuated for medical care.

The Taliban claimed responsibility for the insider attack in the volatile district of Achin, saying it was carried out by an infiltrator.

White House press secretary Sean Spicer said President Trump's national security team briefed him on the situation.

Spokesman Zabihullah Mujahid claimed on Twitter that four U.S. soldiers were killed in the attack. "Additional information will be released as appropriate", the statement said Saturday.

It gave no further details of the incident but said it was under investigation.

Currently, there are about 8,400 US troops and another 5,000 North Atlantic Treaty Organisation forces in Afghanistan to train and assist Afghan forces against the Taliban and conduct counter-terrorism missions.

United States and coalition casualties in Afghanistan have become rarer, falling dramatically since the Afghan government assumed responsibility for combat operations in 2014. About 2,000 of them are involved in counterterrorism operations against al Qaeda and the ISIS affiliate in Afghanistan.

Dubbed the "Mother Of All Bombs", the GBU-43/B Massive Ordnance Air Blast was unleashed in combat for the first time April 12, hitting IS positions in a remote area of eastern Nangarhar province.

There are about 8,400 USA troops in Afghanistan.

Hundreds of US Marines recently arrived in Helmand to take over an advising mission as part of a NATO-led coalition training and assisting local forces.

In some cases Afghan troops have been forced to abandon more scattered and rural bases, and the government can claim to control or influence only 57 percent of the country, according to USA military estimates from earlier this year.