U.N. rights envoy Paulo Sergio Pinheiro (2nd R) looks at food prepared for inmates at Insein Prison during his visit to the facility in Rangoon, 12 Nov 2007

Witnesses in Burma say three more activists have been arrested as U.N. human rights envoy Paulo Sergio Pinheiro meets with Burmese military leaders in the remote capital of Naypyidaw.

Witnesses say the activists were arrested Wednesday while handing out anti-government pamphlets at a fruit market in Rangoon, the main Burmese city where protesters rallied in August and September to call for economic and political reform.

Burma's military leaders brutally put down the protests, and now Pinheiro is in the country to investigate how many people were killed and thrown in jail during the crackdown.

The U.N. says Pinheiro has been assured that he will be allowed to visit political prisoners before his scheduled departure from the country on Thursday.

According to Burmese officials, 10 people were killed and nearly three-thousand detained in the crackdown. But diplomats and human rights groups say the true figures are much higher.

During his meetings today, Pinheiro met with Burma's foreign minister and its labor minister, Aung Kyi, who is acting as a liaison between the military-ruled government and detained opposition leader Aung San Suu Kyi.

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