CANTERBURY, England (AP) - Several hundred people were evacuated from Canterbury Cathedral Sunday in one of a rash of scares around the world sparked by the discovery of white powder.

Church staff began evacuating the cathedral - the seat of the Archbishop of Canterbury, spiritual head of the Church of England - around 1 p.m. (1200 GMT), after a worker said he saw a man dropping a white powder in one of its chapels.

Emergency workers wearing chemical protection suits cleared up the powder and took samples for analysis, Kent Police said. Paramedics were also on the scene.

It was not immediately clear what the substance was, and police said they planned to keep the cathedral closed until they could identify it.

Several hundred visitors were inside the cathedral in this southeastern English town when the evacuation began, but no services were underway.

Jitters about bioterrorism and other forms of attack have spread since anthrax cases were confirmed this week in Florida, New York and Nevada.

"We are taking every precaution at this stage and so we have sent in firefighters with protective suits," said a fire department spokeswoman, speaking on traditional condition of anonymity. "It is still too early to say exactly what the powder is."

Among other scares and anti-bioterror measures taken Sunday:

- Cleaning staff at Rio de Janeiro's International Airport in Brazil found white powder on a flight from Frankfurt after passengers left the plane, federal police and health authorities said. Scientists were analyzing the substance, and the 12-member cleaning staff that found it was isolated in a room at the airport.

- In Toronto, authorities stopped a plane at Pearson International Airport when baggage handlers found white powder in the cargo hold. Test results were expected by Monday afternoon, but police said they didn't think the substance was dangerous.

- Belgian Health Minister Magda Aelvoet said preliminary tests showed a powder found in six confiscated letters was not anthrax. The letters were addressed to the Belgian Pharmaceutical Institute and several of its employees; the postal service seized them after finding the powder. Aelvoet said it was likely a prank.

- German Defense Minister Rudolf Scharping said the military was going over its defenses against biological and chemical weapons, and leaders called for increased sentences for anyone caught sending copycat anthrax letters. Scharping assured Germans the military was capable of defending itself from biological and chemical warfare.

- Major newspapers in two Australian states on Sunday began toughening and reviewing security, particularly mail handling procedures.