Guinea-Bissau speaker is sworn in

Raimundo Pereira must organise a new presidential election within 60 days

Guinea-Bissau's parliament has elected the speaker as the West African state's interim leader, a day after the president was assassinated.

Raimundo Pereira must organise a fresh presidential election within 60 days.

President Joao Bernardo Vieira was shot dead by soldiers who blamed him for a bomb attack that killed the army chief on Sunday.

The UN Security Council condemned the two killings and urged the government to bring those responsible to justice.

Guinea-Bissau - a major transit point for Latin American cocaine headed for Europe - has been plagued by political unrest since it gained independence from Portugal in 1974.

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Before taking the oath of office on Tuesday, national assembly leader Mr Pereira said Guinea-Bissau was "facing a very delicate situation".

He called on MPs "to assume their responsibility toward the nation".

Lawmakers in the capital Bissau also observed a moment of silence for President Vieira and for the army chief-of-staff Gen Tagme Na Waie.

Life in the city began to return to normal with some businesses re-opening, although shoppers briefly fled two market places in panic after rumours spread of fresh shooting, according to Reuters news agency.

'Fragile situation'

Guinea Bissau swears in new leader

The United Nations Security Council "condemns in the strongest terms the assassinations," the 15-member body said in a statement.

"The Security Council reaffirms its commitment to support the efforts of the government and people of Guinea-Bissau to consolidate democratic institutions, peace and stability in that country".

The statement also said the council "opposes any attempt to change the government through unconstitutional means".

Diplomats representing West African and Portuguese-speaking nations have also said they hope the constitution will be honoured.

Nigerian President Umaru Yar'Adua, who heads the 15-member regional bloc Ecowas, has sent a delegation to the country.

Obituary: President Vieira Haunted by history of crisis

"The fragile political situation in Guinea-Bissau has been further weakened by these events," he said.

Soldiers killed President Vieira early on Monday in an apparent tit-for-tat attack after Gen Waie was blown up in his headquarters hours earlier.

The African Union's Peace and Security Council decided not to suspend Guinea-Bissau when it met in the Ethiopian capital Addis Ababa on Tuesday, as it said the attacks did not represent a coup.

The AU suspended neighbouring Guinea and Mauritania after coups last year.

Guinea-Bissau's army has denied it is launching a coup and has promised to honour the constitution.

Portugal's foreign minister also arrived in Bissau and reportedly said he did not see any need for international military intervention in the country.

Senegalese President Abdoulaye Wade has reportedly sent a plane to pick up Mr Vieira's wife and children and take them to Dakar.

Guinea-Bissau, an impoverished former Portuguese colony of 1.6 million people, has been plagued by coups since 1980, when Mr Vieira himself first came to power in one.

Monday's attack was the second on President Vieira in recent months.

In November, his residence was targeted by soldiers with automatic weapons.

In January, Gen Waie had a narrow escape when unidentified gunmen opened fire on his car.

He reportedly suspected the attack had been ordered by Mr Vieira, as he had just stepped outside after receiving a call from the presidency asking him to come at once.