This article is more than 6 years old

This article is more than 6 years old

A helicopter crash in southern Afghanistan has killed six US soldiers, the deadliest day for American troops in the country since March.

There was no fighting reported in the area where the aircraft came down, Nato said in a brief statement, and Afghan officials including the provincial governor and police chief said the chopper had suffered a mechanical fault.

The Taliban said they had shot down the aircraft, but although they have hit some helicopters in the past, they have also repeatedly claimed technical crashes as successful attacks.

The late afternoon crash in Zabul province, near the border with Pakistan, was in the same district where a plane came down in April killing four American soldiers.

"The helicopter had technical problems and crash-landed in Shahjoi district around 4pm. There were no civilian casualties," said the deputy provincial police chief, Ghulam Jelani Farahi.

Zabul was also the site of a suicide attack in early June that killed three US soldiers, a US diplomat and one other US civilian.

Prior to Tuesday's crash, only one US soldier had been killed this month in Afghanistan. The loss of the helicopter was the deadliest single incident of the year, and the worst day for American troops in nine months.

In March, a helicopter crash killed five US soldiers on the same day that an Afghan policeman gunned down two US special forces trainers.

Overall military casualties have dropped dramatically as Nato countries draw down or end their combat missions, and leave Afghans to lead the fight against the Taliban.

With just a few days left to the end of the year, there have been just over 150 deaths, less than half the 402 military killed in 2012.