Sixteen New York Police Department officers pleaded not guilty to charges of widespread fixing of traffic tickets as well as more serious crimes, in the second scandal to hit the force in a week.

Five civilians were also netted in the nearly three-year undercover probe that involved the wire tapping of more than 10,000 phone calls and resulted in indictments containing some 1,600 misdemeanor and felony counts.

Although most charges were for relatively minor crimes of tampering with traffic tickets to help friends and relations, the probe bared an ugly side to New York's so-called "Finest" just days after the arrest of officers in an unrelated gun-running scandal.

"It's difficult to have to announce for the second time this week that police officers have been arrested for misconduct," Police Commissioner Raymond Kelly said.

"Their misdeeds tarnish the good name and reputation of the vast majority of police officers who perform their duties honestly and often at great risk to their own personal safety."

It was also a rare assault by prosecutors on the police and their powerful union, the Patrolmen's Benevolent Association. Hundreds of police and friends crowded the courthouse entrance in a muscular show of support for the accused men.

Initially the probe began with an undercover operation against a uniformed officer, Jose Ramos, who is accused of using two Bronx barbershops he owns -- both called "Who's First" -- as sales points for "large quantities of marijuana," the District Attorney's office said.

An alleged drug dealer managed the barbershops, used Ramos' car and his phone to organize deals, while Ramos himself is accused of transporting what he thought was heroin, as well as attempted robbery.

Three more civilians and an NYPD sergeant were charged in connection to Ramos' alleged activities.

It was during that inquiry, however, that investigators say they came across a seemingly endless web of officers using their authority to make traffic tickets and parking tickets go away as favors to friends.

"Evidence was uncovered linking a large number of police officers to incidents of 'ticket fixing' or solicitation to 'fix tickets,'" the Bronx district attorney's office said.

"Criminal charges have been brought against only those alleged to be the most serious repeat offenders."

In addition, the investigation exposed an alleged failure by police to arrest an assault suspect who had a police union connection -- and then an attempt to cover up the alleged crime.

Union spokesman Pat Lynch told the New York Post that he was outraged by the probe.

"Right now, this has been laid on the shoulders of police officers," Lynch said. "When the dust settles, and we have our day in court, it will be clear that this is part of the NYPD at all levels."

But Kelly condemned attempts to brush the scandal under the carpet.

"Those actions -- crimes under the law -- can't be glossed over as 'courtesies' or as part of an acceptable culture. They are not. Those who try to rationalize them as such are kidding themselves, especially if they think the public finds it acceptable."

It has been a bad week for the New York Police Department, one of the most sophisticated forces in the world.

On Tuesday, eight serving or retired officers were among 12 people arrested on charges of conspiracy to smuggle assault rifles, handguns and other items worth more than $1 million.

A two-year sting operation by police and the FBI nabbed the alleged gang when it brought in an out-of-state arsenal that included three M-16 military rifles, a shotgun and 16 handguns, as well as cigarettes and slot machines.

The goods were believed by the gang to have been stolen and most of the handguns had had their identification numbers erased, making them more attractive to criminals, prosecutors and police said.