Soldiers arrested Guinea-Bissau's presidential front-runner Carlos Gomes Junior after staging an apparent coup in the chronically unstable west African country, his wife said on Friday.

Gomes, the outgoing prime minister tipped to win an April 29 run-off vote, was whisked away in a pick-up truck after troops assaulted their residence late on Thursday, Salome Gomes said when she returned to the house to collect some belongings.

Soldiers armed with rocket-launchers, rocket-propelled grenades and Kalashnikov rifles also took control of the ruling party headquarters and the national radio station and rounded up politicians, as gunfire resounded in the darkened streets of the capital Bissau on Thursday.

A military source said the arrested political figures were taken to army headquarters at Amura, near the coast of the coup-plagued nation.

The Economic Community of West African States, which has been grappling with a rebellion in nearby Mali, "rigorously condemned" the coup bid.

Former colonial ruler Portugal meanwhile appealed "for a halt to the violence and respect for the law".

The military issued a terse statement on Friday saying the move was in response to a "secret deal" between Guinea-Bissau and Angola, both former Portuguese colonies.

"The events of Thursday occurred because we discovered the existence of a secret military accord signed by Prime Minister Carlos Gomes, interim president Raimundo Pereira, the government of Guinea-Bissau and Angola," it said over state radio.

However, the statement did not say who was now in control of the country.

An associate of Gomes said on Friday that Gomes was "in a very safe place" and unharmed. Pereira's whereabouts remain unknown.

Soldiers patrolled the streets on Friday, clustering outside the finance and justice ministries as well as the headquarters of the ruling African Party for the Independence of Guinea-Bissau and Cape Verde, barring traffic from nearby streets.

Around 100 youths demonstrated outside the Gomes residence to show their "solidarity" before soldiers dispersed them.

Violence had been feared for days in the election period in the country, which has a history of political violence and is known as a major drug trafficking hub between South America and Europe.

Guinea-Bissau's opposition - led by second-placed Kumba Yala, a former president who claims the first round of the election was rigged - have called for a boycott of the April 29 run-off.

"Whoever dares to campaign will be responsible for what happens," Yala warned at a news conference with another four main opposition candidates on Thursday, denouncing what he called "massive fraud".

Gomes garnered 49 percent of the votes in the first round against Yala's 23 percent. The election campaign for the second round was supposed to start on Friday and end on April 27.

The first round was also tainted by the assassination of former military intelligence chief Colonel Samba Diallo, who had been accused of involvement in a 2009 bombing that killed the country's then army chief and prompted the murder of president Joao Bernardo Vieira in a revenge attack.

Since winning independence through armed combat in 1974, Guinea-Bissau's army and state have remained in constant, often deadly conflict, with the result that no president has ever completed a full term in office.

Three have been overthrown and one was assassinated in office in 2009.

The latest election was held after the last president, Malam Bacai Sanha, died in January following a long illness.

Agence France-Presse

(China Daily 04/14/2012 page7)