Turkey's Prime Minister Recep Tayyip Erdogan told a group of journalists that anyone attempting to enmesh him in the rapidly developing corruption and bribery scandal would be "left empty handed", talking about the scandal over bribery for construction projects that has now claimed the dismissal on Wednesday of three government ministers. (AP)

A Turkish prosecutor accused police Thursday of obstructing his pursuit of a high-level graft case, adding to public scrutiny of Prime Minister Recep Tayyip Erdogan’s government as it hunkered down defiantly.

Three ministers have resigned after their sons were among dozens of people detained Dec. 17 as part of a probe into corrupt procurement practices. The investigation has exposed Turkey’s deep institutional divisions and left the pugnacious premier facing what could be the biggest crisis of his nearly 11 years in power.

Erdogan responded Wednesday by replacing half his cabinet with loyalists, while frightened investors sent the currency, the lira, to an all-time low Thursday.

The new interior minister, Efkan Ala, will be in charge of domestic security and is considered especially close to Erdogan, who called the secretive investigation a foreign-orchestrated plot without legal merit and responded by firing or reassigning about 70 of the police officers involved.

In allegations disseminated to Turkish news media in writing, prosecutor Muammer Akkas said he had also been removed from the case, which he described as compromised by police who had refused to comply with his orders to arrest more suspects.

“By means of the police force, the judiciary was subjected to open pressure, and the execution of court orders was obstructed,” Akkas said. “A crime has been committed throughout the chain of command. . . . Suspects have been allowed to take precautions, flee and tamper with the evidence.”

The government and police force did not respond to the allegations.