The city of Pittsburgh yesterday fired a heavy equipment operator charged last month with weapons violations and theft of vehicle inspection stickers.

The firing came a day after Mayor Luke Ravenstahl pledged to improve screening of new hires, and amid a series of legal and ethical issues involving North Side public works employees.

The Department of Public Works had suspended Paul J. Grguras, 47, of Brighton Heights, for five days pending termination, and yesterday officials wrote a letter firing him. Sources said the stated reason for his termination was a failure to reveal on his 1999 application for the equipment operator post that he had three prior felony convictions from the early 1980s.

Those convictions bar him from possessing firearms. But when police visited his house to investigate a co-worker's accusation that Mr. Grguras had sold him a stolen inspection sticker, they found 43 machine guns, rifles, shotguns and other firearms, some with no serial numbers.

A police report indicated that Mr. Grguras sold an inspection sticker to another public works employee, Thomas Tucke.

Mr. Ravenstahl on Thursday pledged to start performing background checks on all prospective hires, to avoid hiring felons. He said the procedure should start within two months, pending consideration of whether it conflicts with any union contracts.

"You want to have a work force that is working for the residents of the city of Pittsburgh, and avoiding negative activity," he said.

Kurt R. Staudenmaier, 36, a tractor operator for the Public Works Department's Redd Up Campaign from Brighton Heights, was arrested in September for possession with intent to deliver prescription medication.

Police reports indicate that he told an officer that he had 19 Vicodin pills that he was selling for $5 each. His trial is set to start Aug. 13.

On May 31, a 19-year-old man named Joseph Sinatra who is listed on police reports as living with Redd Up Campaign Manager Kevin Quigley was charged with possession of contraband and three counts of possession of marijuana with intent to deliver.

Mr. Quigley, 43, of Brighton Heights, posted $300 bond for Mr. Sinatra on June 1, according to Allegheny County clerk of courts records. He could not be reached for comment yesterday.

On July 16, Public Works Director Guy Costa wrote to the city Personnel and Civil Service Commission nominating Mr. Quigley to the post of program manager, formalizing the role he has held with the Redd Up Campaign since early 2006. The letter describes him as "extremely qualified."

The move does not change his $59,129 salary, according to Personnel Director Barbara Trant.

In May, Redd Up Campaign workers were photographed wearing the campaign T-shirts of a City Council member. Five workers were suspended, including Redd Up Campaign driver Ray Sansone, of Summer Hill.

The Ethics Hearing Board found that they violated the ethics code by politicking on city time.