HANOI, Vietnam - Vietnam's Central Highlands remained sealed off Monday by police and security officials following protests by hundreds of ethnic minority Christians over Easter weekend.

Scores were arrested and injured when more than a thousand people took to the streets Saturday in Buon Ma Thuot, the provincial capital of Daklak, in what was supposed to be peaceful prayer demonstrations against religious repression and land confiscation. Most of the indigenous mountain tribes are Protestant.

One witness said some protesters converged on the capital driving tractors, while police said demonstrations drawing 300-400 people each took place at several spots around the city.

State-controlled media reported Monday that thousands of people, including ethnic minority groups, celebrated Easter in the Central Highlands provinces of Daklak, Gia Lai and Kon Tum. There was no mention of protests.

The area has been closed off to all foreigners, with flights to Buon Ma Thuot canceled since Saturday and roads leading into the town blocked. Over the weekend, a U.S. Embassy delegation was forced by police to turn back in neighboring Binh Phuoc province.

Vietnam has blamed "overseas instigation" for triggering the protests, which are a repeat of mass demonstrations in 2001.

"In recent days, some extremists in some localities in Daklak and Gia Lai provinces - with overseas instigation - have engaged in actions of causing social disorder, even assaulting authorities, destroying public welfare projects and property in some villages," Foreign Ministry spokesman Le Dung said in a statement.

Police confirmed that dozens of ethnic minority villagers, collectively called Montagnards, were detained Saturday while scores of people were injured in an area of Vietnam that has been politically volatile over issues of ethnic minority rights.

On Monday, police said the situation in the city was "peaceful," while one Buon Ma Thuot resident said things had returned to normal following Saturday's demonstrations.

International human right groups said they received independent reports from witnesses of violent clashes and multiple arrests.

"We've heard there have been many arrests; many more people are going into hiding," a representative from New York-based Human Rights Watch said.

Vietnam recognizes only a handful of state-sponsored religions and has clashed many times with Buddhists and Christians. International human rights groups allege some ethnic minorities have been persecuted for their beliefs and forced to publicly renounce their faith. The European Union and the U.S. State Department have criticized Vietnam for religious repression.

On Monday, Nikola Mihajlovic, head of the U.N. High Commissioner for Refugees office in Phnom Penh, said 74 Montagnards have crossed the border and sought asylum in Cambodia since January.

In 2001, similar unprecedented protests took place in the Central Highlands, triggering a mass exodus into Cambodia. Nearly 1,000 refugees were accepted by the United States for political asylum. Human rights groups assert that more than 100 people have been jailed in Vietnam for helping organize those demonstrations.

Government officials have blamed the North Carolina-based Montagnard Foundation for organizing both demonstrations. The U.S-based organization was founded by former members of a group of anti-communist Montagnard fighters allied with the United States during the Vietnam War.