DANVILLE, Va. -

Danville police are investigating the city's utilities department.

Officers are looking into whether overtime pay and company credit cards were abused among certain groups within the department.

There are also allegations of improper activities involving contracts.

City Manager Joe King called for the investigation after an internal audit last year brought the inconsistencies to light.

Three workers have been fired and two of them now face criminal charges.

It started in October from an internal audit at Danville Utilities that showed, what the city manager is calling, "irregularities."

The city manager asked the police department to begin an investigation of embezzlement and corruption, according to an arrest warrant for Adrien Roberson. Documents show Roberson denied making the purchases, and said they were at a coworker's house who had recently died.

That's when police pressed charges.

Another employee was charged with tampering with a meter device. Police say, for now all charges against that employee have been dropped. They say the department may restructure because of this investigation.

"I think there is going to be some changes certainly there would have to be closer oversight to make sure this could never happen again," said Captain Dennis Haley with the Danville Police Department.

Police tell WDBJ7 this is a basic investigation, but it's extremely detailed since both the police and utility workers virtually have the same boss, the city manager.

They say this investigation will continue for a while.