Criminal psychologist Rosen Yordanov says he has evidence that Ivaylo Kalushev offered 153,388 euros (300,000 leva) to Sofia mayor Vasil Terziev in messages about protecting Vitosha nature park, he said in an interview. He said the sum was an offer to the mayor of Sofia.

This report follows our earlier story on the data from phones in the Petrohan case, which investigators still cannot access.

Yordanov's team carried out the expert report on the Petrohan–Okolchitsa case. The messages between Kalushev and Terziev have leaked. Yordanov says they most likely date from the election campaign or from the very start of the mayor's term.

The psychologist wants to know what exactly the person who made the offer meant, as the messages talk about protecting the park and about an idea and a decision.

Analysing the material took six and a half months, Yordanov said. The report covers many documents, audio and video files, and about 3–4 terabytes of data cannot be opened.

The people involved mainly used the encrypted app Signal. Their devices were reset to factory settings shortly before the fatal events, so investigators largely cannot reach the digital traces.

Yordanov said he will not step down from the case. He said the presentation of the report took place in an abnormal atmosphere. According to him, people who were let into the room booed, and he got into a shouting match with them. Their presence gave an impression of disorganisation and chaos.

Yordanov believes both the people involved and their families are still silent about their own mistakes. Institutions must answer to the public, he added, but others also have to say how they behaved as parents and how they made their decisions.

The grief of the families is being used, the psychologist believes. Many people want to bring those affected together, so relatives of the victims stand next to relatives of the people he calls killers. Yordanov called this absurd and shocking.

The father of one of the victims wants an exhumation. Yordanov said it is terrible for him to think about what this man has been through.