THE ghost of communism has resurfaced in Bulgaria, with 11 of the country's 15 top bishops exposed as former secret police agents, shaking the Bulgarian Orthodox Church and its image just as it readies to choose a new patriarch.

A list published by the parliamentary archives committee has singled out 97-year-old Patriarch Maxim and three other bishops as the only members of the church's top authority, the Holy Synod, not to have collaborated.

The other 11 were listed by the committee as agents of the most notorious part of the feared Darzhavna Sigurnost - the political police which spied on people for suspected "anti-communist behaviour".

The archives law does not entail any legal consequences for the former agents, but Prime Minister Boyko Borisov was quick to declare himself "shocked".

Meanwhile, a handful of ordinary priests from southwestern Bulgaria slammed their leaders in a declaration on Friday, calling them "apostates" who had opened "a festering wound in the church" and urged them to resign.

For Kalin Yanakiev, a philosophy professor at Sofia University and editor-in-chief of the religious magazine Christianity and Culture, the church was a victim of Darzhavna Sigurnost, which "picked up, nurtured, promoted and appointed the bishops".

"Bishops are for life, they cannot resign," he told Bulgarian national television.

But he urged the clerics to repent.

Theologist Nikolay Mihaylov echoed the view.

"It is inadmissible how they agreed to collaborate in full consciousness that they were in the church to ruin it," Mihaylov fumed in a television debate on the subject.

For both analysts, the committee's list of bishops who collaborated may not even be complete.

Many in Bulgaria were surprised for instance that the patriarch, who was appointed in 1971 under communism, was not on the list.