The private bank safety vault in the Bulgarian capital Sofia, which was robbed during the night Monday, is one of the oldest ones, dating from the first years after the fall of the Communist regime.

Until now, the safety vault had been considered one of the most secure in Bulgaria and had long-term customers, keeping there an unidentified, but large amount of valuables, cash and documents in 1 000 safety deposit boxes.

The owner of the vault, which is located in downtown Sofia, on "Evlogi and Hristo Georgievi" boulevard, is identified as Borislav Ralchev, 51, according to reports of the TV channel bTV.

Ralchev is well-known among the wealthiest Sofia residents and has been often called the biggest "slicker" in the city since almost all rich people trusted him with their money.

The owner gave a monthly interest of 2.4% to customers, who deposited their valuables without asking for an invoice. He was also dealing with investing his clients' money, which could end up being illegal because the law allows only banks to deal with accounts of over 30 individuals.

Police say so far they have not received any complaints against Ralchev, but customers explain about 6 months ago he had stopped answering his phone and granting them access to their own money, triggering threats for law suits from about 20 people.

Records show Ralchev had filed for bankruptcy and has a debt of about BGN 1 M.

The safety vault is open 24-hours a day. In such cases, it is usually very hard to find out the exact amount of the damage because most of the valuables kept in these safety vaults are considered to be acquired through illegal means.

Two men came to the vault at 2 am Monday night, saying they were customers and indicated the safety deposit box they needed open. The guards accompanied them there and at that moment they were attacked, beaten, and tied up. One of them is listed in the emergency Pirogov hospital with serious injuries.