Correia Seabra led a military coup in September 2003 which ousted former president Kumba Yala from power.

Prime Minister of the western African country Carlos Gomes Junior told reporters in Bissau that the revolt had been orchestrated by "certain political circles" who lost legislative elections last March.

He said that "you know what we are dealing with and it is journalists who are saying it is the PRS," without directly accusing the opposition Social Renovation Party (PRS) of being behind Guinea's latest military uprising.

Gomes Junior said the rebel troops were meeting with Foreign Minister Soares Sambu under the mediation of the United Nations' special envoy to Bissau, Joao Bernardo Honwana.

A group of soldiers staged a revolt and opened fire Wednesday in Bissau, capital of Guinea-Bissau, to demand payment for peacekeeping duties. Soldiers loyal to the government armed with automatic rifles took up key positions and patrolled the streets of Bissau.

Gomes Junior was also quoted by Portuguese state radio's African service, RDP-Africa, as saying the renegade troops surrounded a main military building in Bissau.

"The revolt broke out at about 4 a.m. (0300 GMT). The chief of staff's headquarters has been surrounded by the renegades,'' GomesJunior said.

Gomes Junior said the rebellious troops were believed to be soldiers who recently returned from peacekeeping duty with the United Nations in Liberia and were angry about delays in being paid.

"We can't accept demands being made at the point of a gun,'' Gomes Junior said.

Military sources told media that exchanges of gunfire occurred in and around the headquarters of Guinea's armed forces chief-of-staff.

Gomes Jr., whose African Party for the Independence of Guinea and Cape Verde rules in a minority, said his government would "notaccept demands being made at gunpoint," adding that the number of rebel troops was not immediately clear.

Guinea-Bissau, which has a population of around 1.5 million, has had a history of political instability going back to its struggle for independence, achieved in 1974.

Soldiers have repeatedly risen against civilian authorities in recent years in the western African country.

An attempted military coup was put down by loyalist troops in 2001. In September last year, former president Kumba Yala was overthrown by the military in a bloodless coup.

The people of Guinea-Bissau are among the world's poorest, scraping by on an average of 140 dollars each a year. They depend largely on fishing and growing cashew nuts.