Six Pakistani employees of a Polish oil and gas company who were kidnapped last year by the Taliban have been freed, a senior government official said Monday.

The workers from Geofizyka Krakow were kidnapped by the Pakistani Taliban in November 2016 from Dera Ismail Khan.

“They have been freed unconditionally and handed over to us late Sunday,” Political Agent of South Waziristan Agency Zafrul Islam Khattak, told AFP.

Khattak said the release took place with the help of tribal elders who negotiated with the kidnappers based in Afghanistan's eastern Paktika province.

“The kidnappers first handed over the six workers to tribal elders at the border with Afghanistan,” Khattak said, adding that the tribal elders later handed them over to Pakistani authorities.

Pictures of the workers seen by AFP show them sitting in a government office with the official in Wana, South Waziristan's main town.

In 2008, a Polish engineer working for the firm was kidnapped by the Pakistani Taliban near Attock and beheaded several months later.

In May, the same Pakistani Taliban faction released a video of the workers pleading for their lives and a spokesman, Azam Tariq, said the six would not be released until the militants' unspecified demands were met.

Geofizyka Krakow, which has been in liquidation since August, could not immediately be reached for comment on Monday. In May, its parent company, PGNiG, said every effort was being made to find the workers.

Security in Pakistan has improved over the last few years but many of the northwestern areas bordering Afghanistan remain volatile and dangerous, especially for foreigners and those working with foreign companies.