The United Nations' top human rights official is calling on Burma's military rulers to immediately release the people detained last week for protesting higher fuel prices.

Louise Arbour (file photo)

In a statement, U.N. High Commissioner for Human Rights Louise Arbour urged the Burmese government to engage in a dialogue with the demonstrators.

About 50 Burmese activists marched Monday against the fuel price increases in the town of Bago, about 75 kilometers northeast of Rangoon, continuing a series of small protests that began last week mainly in Rangoon.

Some reports from Bago quote witnesses as saying the marchers dispersed without incident and police did not intervene. The French news agency says police detained the protesters for questioning and then released them.

Burmese fuel prices soared this month after the government slashed subsidies that kept oil prices low for years. The move sharply increased the cost of public transportation and some basic commodities.

Burma's government says it arrested about 50 activists who took part in last week's protests. A Thailand-based Burmese rights group, The Assistance Association for Political Prisoners, says at least 100 protesters were arrested.

The U.N.'s humanitarian chief in Burma, Charles Petrie, told the Associated Press the fuel price increase will make it more difficult for many Burmese to survive.

He says almost 90 percent of Burmese live below or near the poverty line of one dollar a day.

Some information for this report was provided by AFP, AP and Reuters.