"A helicopter is dropping shells and teargas," an unidentified witness in the northern port city of Sohar told Gulf News by telephone.
Other demonstrators told Radio France International police opened fire with rubber bullets on protesters calling for political reform in the country ruled by Sultan Qaboos bin Said.
Demonstrations began in mid-January as similar protests overturned leadership in the Arabic countries Tunisia and Egypt.
In a move to appease dissenters, bin Said announced Saturday he had made six Cabinet changes and was raising the country's minimum wage, the reports said.
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