Dozens of Turkish police including high-ranking officers were detained yesterday, accused of spying and illegal wire-tapping of Prime Minister Tayyip Erdogan and his inner circle in what the chief prosecutor said was a concocted probe of an alleged terrorist group.

The former Istanbul anti-terror police chief, himself among those detained and led away in handcuffs, said the incident was entirely political, coming just a few weeks ahead of a presidential election in which Erdogan is standing.

The operation follows a stream of purges targeting the police, judiciary and state institutions which government critics have condemned as a symptom of Erdogan’s tightening grip. Concern about his autocratic style has been fuelled by his intention to boost the powers of the presidency if he is elected.

Police conducted raids in 22 provinces, and officers involved in a separate government corruption probe which emerged in December and led to the departure of four ministers were among those detained.