SOFIA (Reuters) - Bulgaria’s chief prosecutor has ordered more investigations, including into the head of the anti-corruption commission, in a scandal over purchases of luxury properties at favorable prices that has already led some senior politicians to resign.

Chief Prosecutor Sotir Tsatsarov said on Thursday that anti-corruption commissioner Plamen Georgiev is among those being investigated for allegedly making false declarations about the circumstances in which he and his wife acquired an apartment in the capital Sofia.

Georgiev denied any wrongdoing and said he would co-operate fully with the investigation.

Prosecutors will be requesting documents including the title deed and bank records of the mortgage financing in order to clarify where funds for the property purchase had come from, Tsatsarov said.

He also named the wife of Supreme Court of Cassation head Lozan Panov and the son of National Investigation Service director Borislav Sarafov as among those being investigated. Neither was immediately available for comment.

Bulgaria is ranked as the most corrupt European Union member state by anti-graft group Transparency International.

Despite pledges by successive governments to stamp out corruption, it has not yet put a senior official behind bars on corruption charges.

Analysts say high-level corruption is the main obstacle to Bulgaria’s ambitions of attracting more foreign investment and joining the EU’s Schengen free travel zone.

LONG LEAVE

Prime Minister Boyko Borissov said those named by the chief prosecutor on Thursday should either resign or take leaves of absence.

Georgiev confirmed he was taking leave so there could be no suspicion he would in any way influence the investigation.

“I hereby declare that I have always respected the law, and that in my work I have been guided by high moral principles and professional standards,” the anti-corruption chief said.

Last week, the deputy leader of Bulgaria’s ruling GERB party, Tsvetan Tsvetanov, quit parliament after similar allegations.

The scandal had already prompted Bulgaria’s justice minister and two deputy ministers to resign following reports they bought spacious apartments in an upmarket Sofia suburb at below-market prices from the same real estate developer.

All four politicians deny any wrongdoing.

The opposition Socialists, who have boycotted parliament since the middle of February, have repeated their calls for an early election, accusing Borissov’s government of failing to combat high-level graft.