A prominent human rights lawyer demanded Monday that Qatar compensate Dutch-based victims of an al-Qaida-linked Syrian extremist group, saying the Al Nusra group was financed by Qatar-based funding networks, reported The Associated Press.

In a letter sent to Qatar's ruling emir that was seen by The Associated Press, lawyer Liesbeth Zegveld accused the wealthy Gulf state of failing to take action against Al Nusra Front and said: "Qatar is therefore liable for the damages suffered by the victims."

In her letter to Tamim bin Hamad Al Thani, Zegveld alleged that one of the victims was taken hostage by members of al-Nusra near Damascus in December 2012.

The man was repeatedly tortured, forced to watch the executions of two other hostages and subjected to a mock execution. The militants demanded nearly $2 million for his release, before he eventually escaped and fled Syria, and has since been granted asylum in the Netherlands, Zegveld said.

 Western officials also have accused Qatar of allowing or encouraging funding of extremists like the Nusra Front. It also has hosted members of the Afghan Taliban.

Qatar also has backed members of the Muslim Brotherhood, a pan-Arab Islamist organization that many states view as a terrorist group.

The Nusra Front "was only able to arise and maintain its terrorist activities due to the financing provided by Qatar," Zegveld said in her letter. "Qatar supports and facilitates the terrorist organization in various ways."

Zegveld said that if Qatar fails to establish a compensation fund, she will launch legal proceedings against the country, state officials and "other individuals and organizations residing in Qatar that are involved in the financing of terrorism."