The UN's envoy called for the release of all political prisoners

Four of them were freed on Sunday and the fifth on Monday morning.

The five are all members of Aung Sang Suu Kyi's National League for Democracy (NLD), although the opposition leader herself was not freed.

It comes two weeks after United Nations human rights envoy, Paulo Sergio Pinheiro, visited Burma and called for the release of political detainees.

Officials from the NLD confirmed the release of the five men, who were all on the party's central committee.

They said that Than Tun, 82, Nyunt Wei, 81, Soe Myint, 80 and Hla Pe, 77, were freed over the weekend.

Lun Tin, 82, was released on Monday morning, leaving three committee members and Suu Kyi still in detention.

Nyunt Wei, NLD treasurer, told the Associated Press that a senior military intelligence official, Brigadier General Than Thun, had informed him that he and some of his colleagues were no longer detained.

Aung San Suu Kyi has been detained since May

"To show respect, he personally came to the house to officially inform me that restrictions have been lifted," he said.

He described his detention as "part of the job" and said: "I do feel relieved for my neighbours that the guard houses have been removed."

Criticism

The NLD's senior members were all put under house arrest after clashes between their supporters and government backers in northern Burma on 30 May.

After his visit to Burma earlier this month, the United Nations human rights envoy to the country, Paulo Sergio Pinheiro, said Burma should release all its political prisoners.

He also said that Aung San Suu Kyi would not accept her own liberty until 35 NLD members, held since the incident in May, were also released.

The BBC's Burma analyst, Larry Jagan, says that some will see the latest releases as a sign that Burma's military rulers are preparing to try to re-start talks with the opposition.

But he said many diplomats feared it was just another attempt at deflecting international criticism of Rangoon, especially since the current session of the United Nations General Assembly is expected to adopt a tough resolution against Burma in the next day or so.

Burma's Prime Minister, General Khin Nyunt, recently announced a new seven stage "road map" to democracy, involving the drafting of a new constitution.

Pro-democracy sources in Rangoon hope that these latest releases may mean that he intends to involve Suu Kyi and her party in that process.