BOSTON -- Weeks after a Team 5 Investigation into cost overruns by Lawrence's public works director, Massachusetts inspector general called Friday for the city to make changes to prevent similar problems in the future.

In March, Lawrence Mayor Michael Sullivan laid off four city workers to make up for $400,000 in cost overruns. The extra spending was authorized by the city's DPW director, Frank McCann, who failed to get approval from his bosses.

Team 5 Investigates Janet Wu reported Friday that the mayor of Lawrence has referred this case, and the findings of Team 5's original investigation to the state Ethics Commission.

The main project in question involved road and sidewalk improvements on High Street in Lawrence, where McCann's political benefactor, City Council President Patrick Blanchette, happens to live.

A copy of the inspector general's report obtained Friday by Team 5 Investigates said the mayor's office "should have been notified" of the cost overrun, and that McCann's claim that he didn't know about the budget "strains credulity."

The inspector general said McCann disrupted "the city's entire capital improvement program."

McCann remains suspended from his job.

The Mayor tells Team 5's Janet Wu that eight more city workers could lose their jobs in the coming weeks due to this unexpected cost.

The inspector general called on Lawrence to require written approval for all city projects from now on and establish penalties for those who don't.