Bulgaria's former Interior Minister in the GERB Cabinet, Tsvetan Tsvetanov, has been summoned for questioning Tuesday morning by the Sofia City Prosecutor's Office.

The interrogation comes in connection with the charges pressed against Bulgarian police's anti-organized crime unit head, Stanimir Florov.

On Friday, Florov was charged with large-scale bribery by the country's prosecuting authority.

The charges stemmed from reports that the Prosecutor's Office and a number of media have received leaked copies of what is claimed to be classified police documents implicating Florov in facilitating drug trafficking.

The alleged documents have been identified as records of police investigations on Florov's suspected activities facilitating international drug trafficking in Bulgaria in the late 1990s and the 2000s.

In particular, the documents mentioned that Florov had been paid to provide cover up for Middle East drug dealers and for the illegal drug manufacturing in the so-called "Opitsvet" affair in 1997.

Currently Head of the Bulgarian police's Chief Directorate for Fight against Organized Crime (GDBOP), at the time Stanimir Florov was an officer in the unit's predecessors.

Tsvetanov stood firmly behind him, rejecting all charges, and saying the anti-mafia chief was a top notch professional while the move of the prosecution equaled "national treason."

Also on Friday, Florov was temporarily released from duties pending the outcome of the investigation.

The order was signed by caretaker Interior Minister, Petya Parvanova.

Valentin Trifonov will be temporarily in charge of GDBOP.