Police have arrested four employees of the town planning office in Katerini, a city in northern Greece, along with seven private civil engineers, in a bribery investigation covering more than 150 cases.
Officers from the police internal affairs unit say the suspects took more than 130,000 euros ($151,000) in illegal payments.
According to investigators, applicants paid "speed money" of 150 to 400 euros to get their paperwork processed faster. Payments to legalize unauthorized buildings reached as much as 7,000 euros.
The investigation began last December after a complaint against a private engineer. Prosecutors ordered a preliminary inquiry. Local police then found that the engineer had extensive contacts with the planning office and its staff, and the internal affairs unit took over the case.
Planning offices in Greece have long been linked to bribery, especially over the legalization of illegal construction.