MIAMI (AP) _ Reported sightings of Andrew Cunanan poured into police phone lines Thursday, leading investigators to believe that the prime suspect in the slaying of Gianni Versace was still in the South Florida area.

One sighting came from a man who said he saw someone fitting Cunanan's description running from a home where a gay doctor was slain in a neighborhood 15 miles from where the fashion designer was gunned down.

By late Thursday, however, police said the killing of the doctor was not linked to the Versace slaying. ``It is definitely not connected,'' said John Coffey of the Florida Department of Law Enforcement.

The reported sighting, though, sent FBI agents and police scrambling to the home near Miami International Airport where the doctor's body was found in his bedroom.

Metro-Dade homicide Sgt. Lou Alvarez said Dr. Silvio Alfonso, 44, a Cuban-born physician, had not been shot, but died from ``trauma to the upper part of his body.''

Versace was shot twice in the back of the head Wednesday outside his oceanfront villa after a morning walk.

Investigators who believe Cunanan is still in the area playing a deadly game of cat and mouse put a close watch on Miami's busy airport, seaport and bus terminals to head off an escape, and warned South Florida residents he could be nearby.

``We strongly believe he is still in this area,'' said FBI spokeswoman Anne Figueiras. ``We urge the public to be very cautious. He is armed and dangerous.''

Coffey said tips about Cunanan's whereabouts were constant on Thursday, leading authorities to believe that Cunanan had not yet left Florida.

Experts on serial killers warned the intense international publicity surrounding the 27-year-old Cunanan, who has been accused of preying on wealthy gay men, could be fueling his ego and his blood lust.

``I would say he's euphoric at this point. If we don't stop him, he will kill again,'' said Jack Levin, who heads Northeastern University's Program for the Study of Violence and is the author of three books on serial killers.

Described by his mother and police as a gay prostitute, Cunanan is also suspected of four murders in Minnesota, Illinois and New Jersey since April 29. He has been charged in three of those cases, the latest charge coming Thursday in the May 3 slaying of millionaire Chicago developer Lee Miglin, who police say had been stabbed and tortured.

While those crimes drew attention, the brazen slaying of Versace put Cunanan in the international spotlight.

Authorities are also studying a blurry videotape from a security camera at the Tides Hotel near Versace's home that showed someone in shorts and a T-shirt running down an alley after the slaying.

An attendant at a parking garage where police found a red Chevrolet truck that Cunanan is suspected of stealing from a New Jersey murder victim said the vehicle had been parked there since June 10.

``We didn't have any reason to think it was stolen or anything. Lots of people leave their cars here when they are on vacation,'' said the attendant, who spoke on the condition of anonymity.

Police wouldn't talk about reports Cunanan had been seen in the vicinity of the Versace mansion weeks before the shooting, or that friends have said he may be HIV positive.

Police in the Philippines on Thursday located Cunanan's father, Modesto Cunanan, who fled San Diego, where he had been a successful stockbroker, in 1988 to avoid charges of financial chicanery.

Police in Plaridel, north of Manila, said the elder Cunanan, a Filipino native, told investigators he doesn't believe his son killed Versace. He refused to talk to reporters who went to his home.

Rewards of at least $65,000 have been offered for information leading to Cunanan's capture, including $45,000 from the FBI and various Miami-area agencies and separate $10,000 rewards from New York City Mayor Rudy Giuliani and the Gay and Lesbian Anti-Violence Project.

Versace's family, which prepared Thursday to take his ashes home to Italy, issued a statement saying it was ``profoundly moved by the incredible demonstration of esteem and affection shown by the whole world for Gianni.''

Authorities and gay leaders in San Francisco, New York, West Hollywood and other cities issued pleas for vigilance to the potential danger as the manhunt spread nationwide.

``We've put out fliers in English, Spanish and Chinese,'' said Jennifer Rakowski of San Francisco's Community United Against Violence.

``We are sending a strong message,'' Rakowski said. ``Murderers are not welcome in this community or any other community.''

While police in the Versace case say they don't know what motivates Cunanan, Richard K. Ressler, who has profiled serial killers for the FBI for 15 years, has his own theory.

``The motivation for this is a death wish,'' Ressler said. ``He is suicidal, especially if he's found out he has AIDS. ... What he is really doing is lashing out against the gay community. Now he's taken out an icon of that community.''