ANKARA (AFP) - Turkish authorities on Tuesday arrested dozens of senior police officers in a criminal probe over alleged illegal wire-tapping and forgery, the latest crackdown on opponents of Prime Minister Recep Tayyip Erdogan ahead of presidential polls.

A total of 67 serving and former top police officers were arrested, prosecutors said in a statement. Most of the arrests were in Istanbul but raids were also carried out in the capital Ankara and cities including Izmir and Diyarbakir.

Television reports said that the arrests represented a new sweep against the movement of Mr Erdogan's former ally Fethullah Gulen in the wake of a vast corruption scandal that broke late last year implicating the prime minister and his inner circle.

Most of the suspects are said to have held key positions during the anti-graft probe against Mr Erdogan in December.

In the huge operation conducted in the early morning, police in Istanbul alone raided almost 200 addresses.

The Hurriyet daily said on its website that simultaneous raids were conducted in 22 cities across Turkey.

Television pictures showed the senior police officers being led in handcuffs with some raising their hands above their heads in a show of defiance.

Among those arrested in Istanbul were two former heads of the city's elite anti-terror unit Omer Kose and Yurt Atayun.

"I surrendered but as you see they put the handcuffs behind my back," Atayun told reporters. "It is all political," he said when asked why he was detained.

The suspects are accused of espionage, illegal wire-tapping, forgery in official documents, violation of privacy, fabricating evidence, and violation of secrecy of investigation, the reports said.

The public prosecutor's office in Istanbul said in a statement that arrest warrants had been issued for 115 suspects and 67 were detained so far.

It said thousands of people were illegally wire-tapped including Mr Erdogan, cabinet members, as well as the head of Turkey's National Intelligence Organisation (MIT) Hakan Fidan.

Mr Erdogan has accused supporters of Mr Gulen of holding excessive influence in the country's police and judiciary and concocting a graft scandal to unseat his government ahead of March local polls.

Mr Erdogan's Islamic-rooted Justice and Development Party (AKP) scored a decisive victory in those local polls, and the prime minister is now standing in elections for president to be held on Aug 10.

After 11 years in power which has seen his government tame the influence of the once-powerful military, Mr Erdogan has declared a war against Mr Gulen, accusing him of running a "parallel state".

In a television interview late on Monday, Mr Erdogan bitterly vowed that the fight against the Gulen movement would continue "non-stop" while calling on the United States to extradite the exiled cleric from his base in Pennsylvania.

"I expect the United States to take a stance on the Gulen issue," Mr Erdogan said.

Mr Erdogan has faced the worst crisis of his over decade-long rule after allegations that he and his allies engaged in corruption which ranged from bribery to gold smuggling and illicit trade with Iran.

His Islamic-leaning government has already sacked thousands of police and prosecutors believed to be linked to the movement in the wake of the scandal and tightened controls over the judiciary and the Internet.

Mr Erdogan and Mr Gulen were once close allies who transformed the political landscape of Turkey, which for decades was ruled by secular governments closely watched over by coup-happy generals.

Gulenists, said to number in the millions and known for their piety and business acumen, say their faith seeks to merge a "civil Islam" with modernity, science and Turkish nationalism.

Mr Gulen, who left for the US in 1999 to escape charges of anti-secular activities by the government of the time, has denied being behind the graft allegations against Mr Erdogan.