Victoria - The Seychelles government ordered schools to close on Friday, after the discovery of two suspected cases of plague thought to have been brought from Madagascar where the disease has killed scores.The health ministry has also put under surveillance 320 people who have come into contact with the two patients.A total of 12 people showing plague-like symptoms have been admitted to hospital and given antibiotics.Panic gripped parents on the Indian Ocean archipelago after some students developed fevers in recent days, leading to the school closures."We made this decision as a precautionary measure to reassure parents," said Merida Delcy, an adviser to the education ministry, noting that they would not reopen until Wednesday at the earliest.Preliminary tests on the two people, including a Seychellois who returned from Madagascar a week ago, showed they could have plague, the health ministry said."It has not yet been confirmed that the two people are sick due to plague, samples will be sent this weekend to the Institut Pasteur (in France)," said public health commissioner Jude Gedeon.The results are expected next week.The sick include a student at Anse Boileau Elementary School on the main island of Mahe where all students have since been given antibiotics.As fear of plague spreads, there has been a run on surgical masks which people hope will offer protection against the highly infectious disease.Plague outbreaks are common on Madagascar, 1 800km to the south, where the disease is endemic. But this year both bubonic plague, spread by infected rats via flea bites, and the pneumonic type, spread person-to-person, have hit urban areas, including the capital Antananarivo, leaving at least 54 dead.A Seychellois basketball coach who was visiting Madagascar is among the victims. The Seychelles government has begun to quarantine people who have arrived from Madagascar in the last week.The latest Madagascar health ministry report this week says 500 cases and 54 deaths have so far been recorded, with around half of each occurring in the capital.