Dozens of Bulgarian miners were trapped below ground after an Austrian energy provider turned of the mines electricity supply over unpaid bills, it has emerged.Bulgarian newspapers revealed yesterday (Weds) 80 workers were caught in shafts in the Balkan 2000 mine near the town Tvardiza for more than four hours on 28 December after Maria Enzersdorf-based EVN cut off the power supply.The Lower Austrian company explained the Bulgarian company running the mine had amassed debts of 8,500 Euros, while Hristo Sosserov, the director of the facility, claimed the outstanding sum ranged around just 500 Euros. Sosserov hit out at EVN for not warning his company in advance that it would stop supplying electricity. EVN apologised for the incident.Sosserov said he decided to set up an emergency power backup in a reaction to the unfortunate occurrence in which no one was seriously harmed. It has not been reported whether the businessman considers stopping abandoning cooperation with EVN due to the incident which made headlines in both Bulgaria and Austria.EVN is one of Austrias leading energy providers. It operates in several countries in Central and Eastern Europe (CEE). The firms earnings before interest and taxes (Ebit) rose by 6.9 per cent year on year to 187.3 million Euros in the 2009/2010 business year which ended on 30 September, while its turnover improved by 0.9 per cent to 2.752 billion Euros.