By SIMON ROMERO

PÔRTO ALEGRE, Brazil, Feb. 3 — A police squad in São Paulo brought an end to the highest-profile case in a recent wave of Brazilian kidnappings by freeing the advertising tycoon Washington Olivetto late Saturday night from a deserted home on a residential street there.

The raid ended nearly two months of captivity for Mr. Olivetto, a dapper 50-year-old who is one of Latin America's leading advertising executives. His agency, W/Brasil, has been recognized as a trendsetter in Brazil's vibrant advertising industry.

Earlier, the police arrested six people in a rented country house near São Paulo who were suspected of taking part in the kidnapping. The property's landlord contacted the police on Friday after growing suspicious that the tenants, who paid the rent in advance and in dollars, were involved in illicit activities.

The police said the suspects might have links to guerrilla organizations in neighboring countries, but they did not provide many details to back up their suspicions. The six suspects reportedly speak Spanish as their native language instead of Portuguese, Brazil's official language.

"They came into Brazil only to conduct kidnappings," said Wagner Giudice, an organized-crime investigator with the São Paulo police.

Mr. Olivetto's release comes as residents of São Paulo, the frenetic center of this nation's economy, have become riveted by a wave of kidnappings.

According to statistics from the São Paulo State Security Bureau, kidnappings climbed to 307 last year from 63 in 2000. Other abductions are believed to go unreported out of fear for the victims' lives or suspicion that corrupt police officials are involved.

Last month, Celso Daniel, mayor of Santo Andre, an industrial city in the greater São Paulo area, was kidnapped and assassinated. A self-described leftist group called the Brazilian Revolutionary Action Front took responsibility for the killing, but little progress has been made in the incident.

Unlike neighboring Colombia, Brazil has had relatively few politically inspired kidnappings and assassinations. Instead, most kidnapping squads in Brazil are believed just to be seeking money. It has become increasingly common for small-business owners or their spouses to be kidnapped and released in exchange for ransom payments generally around $10,000.

Mr. Olivetto was kidnapped in December, when a group of armed men dressed in police uniforms captured him outside his office. Negotiators from Control Risks, a kidnapping specialist firm reportedly hired by Lloyds Bank, through which Mr. Olivetto acquired a kidnapping insurance policy, communicated with the group in coded messages in the classified advertising section of a São Paulo newspaper.

Mr. Olivetto's kidnappers are said to have sought a ransom of $10 million, which his family and business partners were prepared to pay, the police said. But Gov. Geraldo Alckmin of São Paulo State said the ransom for Mr. Olivetto had not been handed over.

Mr. Olivetto, shaken and showing signs of exhaustion, was found in the deserted home on Kansas Street in Brooklin, a residential and commercial district of São Paulo, after some his captors fled when they learned of the earlier raid on their associates. A neighbor heard Mr. Olivetto pounding on a wall.

Mr. Olivetto's kidnapping and subsequent release shares similarities with another high-profile kidnapping of a Brazilian executive in 1989. In that incident, a group of Chileans, Canadians, Argentines and one Brazilian abducted Abílio Diniz, the owner of a large supermarket chain. Mr. Diniz's kidnappers had planned to use the ransom to finance guerrilla activities in El Salvador, but they were thwarted when the police rescued the executive after six days of captivity.