Warrants have been issued to those with suspected links to the network of the US-based Muslim cleric Fethullah Gulen, who is accused of orchestrating the attempted coup in 2016, the source said.
The raid is currently ongoing, covering 75 cities across Turkey.
The suspects are accused of having an active role in the 2010 cheating scandal involving an exam police officers must take to become police inspectors.
At least 45 people who are suspected of obtaining the questions prior to taking the exam allegedly hold office in Ankara.
This is a developing story and will be updated.