Described as a man who prefers the night, Peru's shadowy intelligence chief Vladimiro Montesinos has suddenly been thrust into the light — and the brightness is revealing ugly things.

A videotape that appears to show him bribing an opposition congressman may have brought his years of behind-the-scenes power to an end — as well as loosened his boss' decade-long hold on the presidency. 

President Alberto Fujimori announced he was deactivating the National Intelligence Service on Saturday, then told stunned Peruvians that he was calling new elections and would not be a candidate. 

Although Montesinos was never officially the head of the National Intelligence Service, he controlled the agency completely, transforming it into this nation's most feared and vilified institution. 

Most see the agency's deactivation as a clear message that Montesinos has been pushed aside, and many Peruvians note the irony in Montesinos' fall: he was betrayed by colleagues within the intelligence agency who provided the videotape to an opposition congressman. 

The balding Montesinos, 54, is said to have thousands of tapes of public figures in compromising positions. Secrets are his stock in trade. He ran a spy network that provided him with information that he allegedly used against opponents to bend them to his will. 

For years, Montesinos was the shadow at Fujimori's ear, always close by but out of the public eye. He was accountable to no one except the president. Rarely seen during the day, he usually met with Fujimori before dawn. 

Fujimori's critics say Montesinos has manipulated Peru's intelligence network to illegally infiltrate all branches of government for Fujimori — and they have accused him of masterminding a campaign of smear attacks and dirty tricks to assure Fujimori's re-election. 

Opposition leaders demanded his immediate arrest after the videotape was aired. But Prime Minister Federico Salas said Sunday that Montesinos was still free in Lima — although under investigation. 

What role the military would play in the political shake-up was unclear. Fujimori was in full control of the armed forces, Salas said. But Montesinos hand-picked Peru's top generals, and it may be that their allegiance to him is stronger. 

"Montesinos controls the armed forces, the judicial system, the attorney general's office," political scientist Fernando Rospigliosi said. "He has immense power, more than Fujimori." 

In a sign of Montesinos' continued grip on power, retired army Gen. Daniel Mora noted that two television stations "that are practically run by the intelligence service" did not broadcast Fujimori's speech to the nation. 

However, he said he did not think there was a military crisis. 

"The president is still the commander in chief of the armed forces," Mora said. 

Montesinos had a dark past when he hooked up with Fujimori in 1990 during Fujimori's first run for the presidency. 

Montesinos was cashiered as an army captain in 1977, accused of selling military secrets, and served a year in military prison. After his release he picked up a law degree and made his living defending drug traffickers. 

In 1996, a major drug trafficker accused him of taking payoffs of $50,000 a month but later recanted his trial testimony. Montesinos' intelligence service also has been linked to death squad killings and torture. 

Francisco Loayza, a former intelligence agent who has written a book about Montesinos called "The Dark Face of Power," said he introduced Montesinos to Fujimori when Fujimori faced an unexpected tax investigation during his first campaign. 

He said he knew Montesinos could torpedo the investigation through his contacts in the judicial system. And within three days, he had resolved the problem, Loayza said. 

Hernando de Soto, an economist who worked closely with Fujimori in his first term, said it may be difficult to dislodge Montesinos from power. 

"He's Peru's most unpopular man and its most accused man," de Soto said. "They're going to be after him with bloodhounds when this is over, so, of course, he doesn't want it to be over."