(Bloomberg) -- A Swedish court has found a Turkish national guilty of attempted extortion on behalf of the militant Kurdish group PKK, in a case that the leadership of the Nordic country could seek to use in efforts to persuade Turkey to ratify its application for NATO membership.

The Stockholm District Court on Thursday sentenced the man, Yahya Gungor, to four years and six months in prison for attempted extortion, an aggravated arms offense and trying to raise funds for a terrorist group. He will also be extradited to Turkey after serving his sentence.

Read more: Sweden Pins NATO Ambitions on Terror Law to Sway Erdogan

The verdict comes on the same day as foreign ministers from Finland and Sweden meet their Turkish counterpart at the NATO headquarters in Brussels, seeking to persuade his government to ratify Sweden’s application to join the North Atlantic Treaty Organization. Turkey has refused to do so, arguing that the Nordic country hasn’t done enough to thwart activities of terrorist groups such as the PKK. 

After allowing arms sales to Turkey and introducing stricter anti-terrorism laws, Sweden insists that it has fulfilled its obligations under a deal clinched last year to break the impasse.

Read more: Turkey Demands Sweden Expel Kurd Suspects Before NATO Entry 

The verdict announced Thursday stems from an incident in January, when Gungor entered a Stockholm restaurant, threatened a Kurdish staff member and fired a revolver. When he was arrested a few weeks later, police found ammunition and a large PKK flag in his apartment, while the revolver was retrieved below his balcony.

“The investigation shows that the PKK is running very extensive money-collection activities in Europe, which includes extortion targeting Kurdish business owners,” the court said in a statement. 

“A senior PKK leader is deemed to have been in Stockholm and participated in deciding that the plaintiff were to pay money to the PKK,” according to the statement. “The investigation shows a clear connection between the PKK leader and the defendant, making it clear that they acted jointly to force the plaintiff to hand money over to the PKK.”

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