Updated

The Pennsylvania State Police academy revealed Wednesday that 29 cadets have been forced out of the program following a cheating investigation.

Pennsylvania State Police Commissioner Tyree Blocker declined to reveal further information about the probe into the academy’s 144th graduating class, citing an ongoing investigation. Nearly 70 other cadets are scheduled to graduate in mid-March.

"We're working very diligently at bringing some closure to the investigation," Blocker told reporters. "However, I want to be clear. We will not leave any stone unturned when it comes to the integrity of the Pennsylvania State Police."

Some of the 29 were dismissed and others resigned, he said.

Cadets face a bevy of written tests during training. Blocker said a discovery by the academy staff prompted the investigation and that the testing process was compromised. He didn’t specify the manner of cheating that is under investigation or what spurred the probe.

Blocker first disclosed on Feb. 4 that the internal affairs unit was conducting a "full and comprehensive" investigation. He said the investigation began in December and involved dozens of interviews and an extensive collection of evidence.

With more than 6,000 uniformed and civilian personnel, the Pennsylvania State Police is one of the nation's largest law enforcement agencies.

According to The Patriot-News, cadets receive a $1,200 biweekly salary while at the academy. After they graduate from the program, cadets are assigned to a troop and start an 18-month probationary period. Whether they graduate or are dismissed, cadets are not required to pay back training costs, the paper reported.

The Associated Press contributed to this report.