Safety fears restrict relief work after Myanmar riots SITTWE, Myanmar (Reuters) - Armed troops patrolled the northwest Myanmar city of Sittwe on Friday after days of sectarian violence that has stoked nationalist fervor and displaced 30,000 people, with many feared dead. Heavy rain kept many residents indoors in the Rakhine state capital and police and aid groups struggled to get food to thousands of ethnic Rakhine Buddhists and Muslim Rohingyas displaced by communal rioting and arson that have presented a big test to Myanmar's 15-month-old quasi-civilian government. United Nations officials told Reuters three of its staff, two from its UNHCR refugee agency and one from the World Food Programme (WFP), all Myanmar nationals, had been detained by police in the Rohingya-dominated town of Buthidaung for unknown reasons. The WFP had provided hundreds of sacks of rice to some areas, said Aye Win, spokesman for its operations in Myanmar. We will try to get to other camps as soon as we can, when it is safe and secure. We are doing as much as we can. We will go in but security is paramount," he added. More than 20 houses were burned down late on Thursday in a village near Sittwe, residents said, adding to the 2,500 torched in the past week. But there were no reports of further deaths. The violence, which the government said had killed 29 people and displaced 30,000 as of Thursday, is a major setback for a rapidly reforming Myanmar that has seen a year of dramatic political change after 49 years of oppressive military rule. The new government has made peace and unity among Myanmar's many ethnic groups its mantra and has struck ceasefire deals with minority Karen, Shan, Mon and Chin rebels, among others, after decades of hostilities. The Muslim community's Friday prayers were cancelled in Sittwe and surrounding villages to avoid a repeat of riots that erupted in the town of Maungdaw a week ago and spread to other parts of Rakhine state. Officials do not want large gatherings and want to avoid more violence. They (Muslims) will be able to pray at home," Shwe Maung, a Muslim member of parliament for the ruling Union Solidarity and Development Party, told Reuters. What triggered the rampage of rock-hurling, arson and machete attacks is unclear and the subject of heated debate, with protests taking place in other regions and Facebook pages and Internet web boards inundated with inflammatory comments. There is entrenched, long-standing animosity in the state bordering Bangladesh between Rakhine Buddhists and stateless Muslim Rohingyas, of whom there are an estimated 800,000, most living in abject conditions. Bangladesh, like Myanmar, does not recognize Rohingyas as citizens and the Bangladeshi authorities have turned away more than a dozen boats with Rohingyas fleeing the violence this week. The crisis has put President Thein Sein in a tight spot. His government is under pressure from rights groups and Western countries to show compassion towards the Rohingyas but if there is any change in policy towards them, it could face the wrath of the public, many of whom regard them as illegal immigrants. A dawn-to-dusk curfew remained in place in Sittwe and many Rohingyas had been moved out by security forces, said Hla Maung, who is in charge of a camp looking after Rakhine Buddhists, close to a near-empty Rohingya neighborhood. On a visit to the Philippines, Myanmar Foreign Minister Wunna Wunna Maung Lwin told Reuters everything was being done to ensure the situation remained stable. We have taken care of everything, we give priority to the stability of the state. Sittwe is back to normal," Wunna Maung Lwin said. Nobel laureate and opposition parliamentarian Aung San Suu Kyi expressed concern over the violence on Thursday. Speaking in Switzerland on the first leg of a five-country European tour, she sidestepped a question about whether she supported granting citizenship to Rohingyas and said resolving the Rakhine conflict required "delicacy and sensitivity." Relations between the two communities have always been uneasy and tension flared last month after the gang rape and murder of a Buddhist Rakhine woman that was blamed on Muslims. Reporting by Reuters staff reporters; Additional reporting by Manny Mogato in Manila; Writing by Martin Petty; Editing by Alan Raybould and Jonathan Thatcher