More than 3,000 Omani protesters took to the streets of the southern city of Salaleh on Friday, demanding political reforms and greater freedoms, dpa reported.
Protesters chanted "Freedom!" and "The people want to bring down corruption" as they marched through the streets of downtown Salaleh towards the Dhofar government building.
They also demanded the trial of former ministers sacked in recent cabinet reshuffles, accusing them of corruption.
Friday protest marches have become a regular event in Salaleh in recent weeks, beginning after noon prayers.
Earlier this week, Sultan Qaboos bin Said Al Said ordered the release of over 280 protesters - who had been detained in recent months - in an attempt to appease demonstrators.
At least two protesters were killed in clashes with security forces in the northern town of Sohar in February.
In a bid to defuse the unrest, Sultan Qaboos has ordered the creation of 50,000 new jobs, proposed broad reforms to the country's political and legal system and sacked several ministers holding key portfolios.
Oman has witnessed frequent protests since February, inspired and encouraged by successful anti-government movements in Egypt and Tunisia.