Targets reportedly included government ministers and business leaders.
The prosecutors, who are said to be loyal to US-based cleric Fethullah Gulen, have denied the accusations.
Gulen has been accused of running a "parallel state" in Turkey, controlling groups of police, lawyers and politicians. He denies the claims.
The latest allegations came in two pro-government newspapers, Yeni Safak and Star.
The Star reported that "Gulenists" had wiretapped more than 7,000 people since 2011 on the pretext of trying to uncover terrorism plots.
One of the prosecutors named in the stories, Adem Ozcan, denied the allegations.
"There was definitely no monitoring or phone-tapping of thousands of politicians, writers, NGO representatives and businessmen in the framework of this dossier in the way that the newspaper stories say," he said in a statement.
Gulen has denied using his influence to start investigations into allegations of government corruption.
Prime Minister Recep Tayyip Erdogan has accused Gulen, a one-time ally who lives in self-imposed exile in the US, of trying to attack the government.
Four ministers have resigned in the aftermath of the corruption inquiries.
Erdogan has pledged to fight on, in what is seen as the biggest challenge to his government in his 11 years in office.
BA/BA