SARAJEVO (Reuters) - A Bosnian court said on Thursday it had rejected a request from Tunisia to hand over a Bosnian national wanted on terrorism charges over his alleged role in the 2016 killing of a Tunisian whom Palestinian group Hamas said was one of its members.

The state court concluded that Elvir Sarac, who was arrested this week on Interpol’s red warrant, could not be extradited to Tunisia because the two countries have no bilateral treaty allowing extradition of their nationals for prosecution.

Neither Bosnia or Tunisia are signatories to international conventions which could provide for extradition under special circumstances, the court said in a statement to Reuters. It did not provide more detail on further proceedings.

Bosnian judge Branko Peric has said Sarac was suspected by Tunisia of “instigating terrorist acts and of membership of a terrorist organization, as well as of harming public order and international security”. Sarac has denied any wrongdoing.

Mohammed Zawari, an aerospace engineer and drone expert, was shot dead in December 2016 near the city of Sfax. Tunisian authorities said they had arrested 10 Tunisians but that two foreigners suspected of plotting the killing had escaped.

Hamas blamed Israel for the killing of Zawari, who had been a member of its organization for 10 years, it said.

Police in Croatia arrested a Bosnian citizen wanted by Tunisia for the same assassination in March.

A Croatian court ruled last week that he could be extradited to Tunisia, although his lawyers said they would appeal.