Six crew members of a Pakistani government helicopter taken hostage after it crash-landed in Afghanistan's volatile east have been released, an official said Saturday.

The crew "was released in an inter-tribe exchange on the Pakistan-Afghan border (and) arrived in Islamabad today," foreign ministry spokesman Nafees Zakaria said in a statement.

He did not specify who had been holding the crew hostage nor what kind of exchange had secured their release.

All six people -- five Pakistanis and a Russian navigator -- are "safe and in good health," he added.

A senior Pakistani official, speaking on condition of anonymity, confirmed the crew's safe return.

After the August 4 crash, local authorities in Afghanistan said that the six-person crew had been taken hostage by the Taliban.

Militants set the Mi-17 transport helicopter on fire and took the crew to a Taliban-controlled area after it made an emergency landing in Logar province.

The crew included retired Pakistani military officers and a Russian navigator, Pakistan's Dawn newspaper reported at the time.

Pakistan had sought permission to fly a helicopter, being sent to Russia for overhauling, over Afghan air space.

Kabul has long accused Pakistan of supporting the Taliban and continuing to nurture sanctuaries on its soil in the hope of maintaining influence in Afghanistan.