By LARRY ROHTER
 
BUENOS AIRES - He was a 23-year-old engineering student from a middle-class family, kidnapped one night early this year on his way to see his fiancée. Days later, while held for ransom, he managed to escape, but when neighbors alerted the police to a man running down the street calling for help, they say they were ordered back into their houses and told to mind their own business.

Only later, after the student, Axel Blumberg, was fatally shot in March, did an explanation for that seemingly strange police behavior emerge. Two senior members of the Buenos Aires provincial police were charged with complicity in the case, and an investigating magistrate says others in the local precinct have also been implicated in the act, which is believed to have been carried out by an organized-crime gang.

For Argentines, the Blumberg case has become a scandal so heinous that it has led to protest marches and the formation of civic groups. But current and former police officials and Argentine criminologists said the only aberrations were the exposure of the misdeed, its fatal conclusion and the outraged public response. What was apparently the involvement of the police, they said, is actually an example of business as usual that could not take place unless it also involved powerful politicians who provided protection.

"This phenomenon has existed and is historic," León Arslanian, the recently appointed minister of public security, said in an interview, in which he pointed to efforts to curb it. "The political class has contributed to the phenomenon of police corruption in various ways."

During his first year in office, President Néstor Kirchner of Argentina has repeatedly pledged to cleanse the Buenos Aires provincial police, a 47,000-member force that he describes as "oozing with pus." At his initiative, purges have been conducted there and within the troubled Federal Police, leading to the removal of hundreds of officers.

More than public security is at stake: the success of his presidency, in fact, may hinge on his ability to bring to heel La Bonaerense, the nickname for the force in the Buenos Aires Province, which is home to nearly 40 percent of Argentina's 39 million people. Top police officials who are protected by powerful politicians are said to be responsible for funneling millions of dollars to Mr. Kirchner's political rivals within the governing Peronist movement.

Mr. Kirchner did not respond to requests for an interview, and Justice Minister Gustavo Béliz canceled an interview to discuss the police cleanup campaign. But in recent public remarks, Mr. Béliz said, "The problem is that the police forces have been corrupted because there have been criminal politicians who have made deals with them."

Mr. Kirchner fired Mr. Béliz in late July in a dispute over how much force should be used in quelling political demonstrations in the capital. Just two days earlier, the president had also fired the head of the Federal Police in a related dispute, for refusing to carry out his order not to allow police officers to carry firearms while patrolling at such protests.

Many of the officials who supervise the provincial police say the force is notorious for corruption and despised by the public. A foreign official who has been forced to work with the provincial police describes it as "a mafia in uniform,'' and prosecutors and experts on public security say it is deeply entwined with organized crime.

In the Buenos Aires provincial police, "each division dedicates itself to the area of crime that it is supposed to be fighting," said Alejandra Vallespir, a sociologist at the University of Buenos Aires who has written extensively about the police force. "The robbery division steals and robs, the narcotics division traffics drugs, auto theft controls the stealing of cars and the chop shops, and those in fraud and bunco defraud and swindle."

Prosecutors and former police officials say there is not an area of crime, from prostitution and gambling to drug-running and kidnapping, in which members of the provincial police force are not involved. On roadways and in the pampas, so-called "pirates of the asphalt," sometimes in marked patrol cars, are engaged in cattle rustling and highway robbery.

In an interview in the provincial town of Mercedes, Miriam Rodríguez, a crusading prosecutor who has obtained numerous convictions for police corruption, including that of her chief personal assistant, described how the system typically works. She cited the case of an auto-theft ring in which she obtained the conviction of seven police officers.

Thieves would steal a car and sell it with fake registration papers to an unsuspecting buyer, she said. The police would then seize the car, threaten the new owner with jail unless he paid hefty bribes, and give the car back to the thieves. The cycle would be repeated sometimes three or four times before the car would be turned over to a chop shop and dismantled.

The sums raised through such schemes are huge: as much as $30,000 a month in profits and bribes from the richest of the province's 300 police stations, according to prosecutors and former police officials. Norberto Fiori, a former precinct chief who admitted his corruption and turned state's evidence after a fallout with colleagues, says the payoffs required for criminal acts are well-established: a typical bordello, for instance, pays the police a $100-a-week fee for each of its prostitutes, while the "commission" for a stolen car is a minimum of $300.

"Each precinct is given a quota that it has to meet, and finds various ways to do that," said Ricardo Ragendorfer, an investigative journalist who is the author of a pair of best-selling books on what he calls "la maldita policía," or cursed police. "Half of the takings stay there, at that level, and the other half goes up the chain to the high command."

But the money does not stop there. Current and former government officials who have been involved in investigations of the provincial police say that much of the graft ends up in the hands of political bosses and party functionaries, mainly but not exclusively Peronists, who use it to buy votes and assure passage of legislation that advances their interests.

By taking on the provincial police, President Kirchner hopes to strengthen himself on two related fronts, government officials and public security experts said. First of all, he needs to restore public security, which was cited as the country's main problem by 64.1 percent of those questioned in a recent poll.

By doing so, he would weaken his main political rival, former President Eduardo Duhalde. Though no longer holding public office, Mr. Duhalde still controls the Peronist machine and the party's large congressional delegation from Buenos Aires province.

Mr. Duhalde did not respond to interview requests. When he was governor of Buenos Aires Province in the 1990's, he described the force as "the best in the world" and thwarted reforms, said officials who worked in the public security area at the time.

Mr. Kirchner, while also a Peronist, comes from a small province in Patagonia. He would like to build an independent political base in Buenos Aires Province, but is said by party officials and Argentine political commentators to see his efforts to consolidate power and past political and economic reforms as being blocked by Mr. Duhalde.

Previous governments have made similar pledges to reform the police and failed to make significant changes. To strike back effectively, Mr. Kirchner needs more allies, but they are hard to find. Many segments of society that might be expected to support reforms, like business groups, have been frightened into silence.

"There is no way this institution can reform and cleanse itself," said Marcelo Saín, a former deputy provincial minister of public security who now is a researcher at the University of Quilmes. "There are simply not police officials with the will to carry out such a task."