Former Police Department spokesman Sgt. David Tammaro, who had been on paid administrative leave since late winter, formally retired from the department last week, several sources said.

But a state police investigation said to involve his use of overtime is continuing.

Chief John Karajanis Jr., meanwhile, now is out on some sort of injury or medical leave, several police sources said. Further details were not immediately available and Karajanis did not immediately return a call for comment.

Tammaro, who was a police officer for 28 years and the police department’s spokesman for several years, was suspended in late February or early March pending both an internal investigation and a state police investigation into allegations involving his use of overtime, multiple sources have said.

He could not immediately be reached for comment.

“I can confirm that Tammaro retired,” said Board of Police Commissioners Chairman Raymond Collins III. “He submitted a letter a couple of weeks ago.”

Tammaro’s retirement was effective Aug. 17, but it wasn’t official until the Board of Police Commissioners met and accepted it Tuesday night, Collins said.

“He’s got 28 years in” and was eligible to retire after 20 years, Collins said.

With regard to the status of Karajanis, Collins said, “I know he’s out right now but ... we’re not really sure of the specifics on it.

“I don’t know if he’s been diagnosed with anything,” Collins said.

Deputy Chief Joseph Perno is in charge of the department in Karajanis’ absence. He also confirmed that Tammaro’s retirement was effective Aug. 17.

Police union President Detective Sean Faughnan said Tammaro “has worked here for 28 years” and has “had 28 years of service. I guess he decided it was time to leave.”

He said that as far as he knew, “there’s been nothing that’s come out” with regard to either investigation.

“Nothing’s come back to us,” Faughnan said.

Police sources have said that the internal and state police investigations appear to center on Tammaro’s alleged use of overtime.

State police did not immediately respond to a request for information regarding the status of the investigation involving Tammaro.

State police former spokeswoman Trooper Kelly Grant previously confirmed that state police were investigating at the request of the state’s attorney’s office.

The internal investigation centers on whether Tammaro broke any department rules. State police are investigating whether any laws were broken, sources have said.

Several sources said that Milford State’s Attorney Kevin Lawlor was involved in the decision to get state police involved.