KIKWIT, Zaire (AP) _ Health workers were searching street-by-street through this quarantined city looking for new cases of Ebola, the lethal virus that has killed at least 87 people.

A Zairian man who arrived in Toronto aboard an airliner from Belfast, Northern Ireland, was put in 21-day quarantine Wednesday after telling officials his mother died in the area stricken by Ebola.

Canadian officials said the quarantine was just a precaution because his mother's symptoms did not appear compatible with Ebola and the man was not exhibiting any symptoms of the disease.

Zaire's government has quarantined Kikwit, a sultry tropical city of 600,000 people. But fearful the virus could spread to Kinshasa, the capital city of 6 million people 370 miles to the west, the government has set up a 20-bed quarantine ward there.

Zaire's president admitted Wednesday there was no way to completely secure Kikwit.

``Those who are in quarantine are not under arrest, and since they are not under arrest they can sometimes escape and do what they want,'' President Mobutu Sese Seko told reporters in Kinshasa.

The president spoke during a visit to a warehouse to see donated medical supplies being sent to Kikwit. He said he wanted to go to Kikwit but his doctors had forbidden it.

Health workers have begun to convince the people of Kikwit that the ritual washing of loved ones' cadavers could transmit Ebola, and now make the rounds in a big orange truck to collect bodies left in the street.

Along with a plastic-wrapped cadaver, one crew Wednesday brought in an old woman, curled up in a folding chair, who was suspected of carrying the virus. No one else would bring her.

``It's really bad,'' said Dr. Mungala Kipasa, a graduate of Tulane University in New Orleans. ``We are finding more and more sick people as we search street by street through the city. There will be many more deaths.''

One person died Wednesday, raising the death toll to 87, according to Dr. Jean-Jacques Muyembe, a professor of microbiology at Kinshasa University. He is in Kikwit overseeing medical services.

Another five people are known to be infected, he said.

The World Health Organization expects a significant rise in the number of Ebola victims soon because of the disease's incubation period, which ranges from six days to three weeks, according to spokesman Philippe Stroot.

There is no vaccine or cure for Ebola, which is spread through bodily fluids and kills 80 percent of those who contract it. Victims die within days with blood pouring from their eyes, ears and noses.

In the United States, the Centers for Disease Control has ordered all airlines to notify the agency if any passengers headed to the United States were ill with fever or vomiting blood, two Ebola symptoms.