Turkish Prime Minister Recep Tayyip Erdogan says a corruption probe in which dozens of people have been detained is part of a "dirty operation" against his administration, linking it to a summer of anti-government protests.
Erdogan's comments come a day after police raided the offices of several prominent businessmen close to his inner circle and detained a number of government officials - including the sons of three Cabinet ministers - in the biggest corruption investigation since he swept to power in 2002.
In a sign that Erdogan was fighting back, he said Wednesday that five top police officials have been removed from their posts in Istanbul for abuse of office, and that more could follow in other cities.
Turkish media reported that police searching the home of the state-run Halkbank's chief executive, Suleyman Aslan, seized shoeboxes stashed with $4.5 million in cash. The bank's office's were raided and Azerbaijani businessman Reza Zarrab, who is married to a Turkish pop star, also was detained.
Deputy Prime Minister Bulent Arinc told reporters that 51 people were being questioned.
Tuesday's raids and detentions are controversial in part because the Istanbul prosecutor said to be leading the investigation, Zekeriya Oz, is believed to be sympathetic to U.S.-based Turkish cleric Fethullah Gulen, whose followers are influential in the police and judiciary.
That has raised suspicions among Erdogan's circle of an anti-government conspiracy.
Tensions have grown in recent months between the Turkish government and Gulen's Hizmet movement over plans to close private test preparation centers, including those run by Hizmet.
Hizmet runs schools in more than 100 countries and owns many of the tutoring centers the government is trying to shut down.
Erdogan told reporters his government is fighting "to make Turkey in the top 10 countries of the world [while] some are engaged in an effort to halt our fast growth. There are those abroad... and there are extensions of them within our country."