By Sarah Rainsford
BBC News, Madrid
Dozens of people were arrested in Monday's operation
The main target of a trans-European operation against a Georgian-organised crime network escaped in Greece on Monday, a Spanish official has said.
Spain's anti-corruption chief said Lasha Shushanashvili got away because of what he called a lack of necessary co-operation from Greek police.
Spanish officials now have no idea where the alleged mafia boss is hiding.
Police in six countries arrested more than 76 men accused of theft, extortion and money laundering.
Spanish officials say most of the crimes, mainly jewellery theft, were committed elsewhere in Europe.
The money was then sent to Spain to be laundered, using a number of businesses including restaurants and a courier service.
Police in Austria believe the gang was responsible for almost a third of all break-ins in Vienna alone.
In Spain, more than 170 police were involved in Monday's raids, the culmination of Operation Java, which lasted more than a year.
They are still investigating the group's possible links to drugs and gun smuggling and say there may be more arrests to come.
It is the third major operation in recent years to target east European mafia groups in Spain.
Media reports say police believe the Georgian gang is linked to an alleged Russian mafia boss who was arrested two years ago and is now on trial here.