The Dutch foreign affairs ministry has withdrawn support from a project in Syria because of concerns that some of the money has gone to extremist groups, the AD said on Wednesday.

The ministry had earmarked €12.5m for the project, some of which would be spend on the Free Syrian Police force, an unarmed police service which is supposed maintain law and order in areas under the control of the Syrian opposition.

However, an investigation by BBC programme Panorama found that some of the cash was being diverted to extremists in Syria.

In particular, the programme found police were cooperating with courts that carry out summary executions – including a case where two women were stoned to death.

It also alleged the police were being paid in cash and then being forced to hand over funds to an extremist group controlling the area. In addition, Panorama said, police officers being handpicked by an extremist group.

Adam Smith International, which has been running the project since October 2014, has strongly denied the allegations, Panorama said.

Germany, Denmark and Britain have also put money into the project, the paper said. Britain has also suspended its contributions.