MADRID (AP) — A major corruption scandal involving politicians has prompted Spanish Prime Minister Mariano Rajoy to apologize to Spaniards.

Rajoy said in Parliament on Tuesday that he understands public indignation over a police operation which has led to the arrest of more than 30 people on suspicion of corruption. Many of them were politicians in municipal and regional authorities who are accused of receiving bribes to grant public construction contracts. The arrests came in a police operation Monday.

In a rare public gesture, Rajoy said he apologized in the name of his governing Popular Party for having appointed officials to posts “they were unworthy of.”

He vowed to clean up public life and asked Spaniards to keep their faith in the rule of law.

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