Guinea-Bissau's parliamentary speaker Raimundo Pereira took oath as the country's interim president on Tuesday, one day after President Joao Bernardo Vieira was killed.

Guinea-Bissau's parliamentary speaker Raimundo Pereira stands during the national anthem at his swearing-in as interim president March 3, 2009. [Xinhuanet.com]

According to the western African country's constitution, Pereira will server as interim president till a new leader is elected. The constitution requires that elections be held within two months.

Guinea-Bissau's President Vieira was killed by soldiers early on Monday after a bomb attack in which the country's military chief was killed.

An unknown number of soldiers apparently launched a retaliatory attack after the armed forces chief of staff, Batista Tagme Na Wai, was killed in an explosion that destroyed part of the military headquarters.

Na Wai, a critic of President Vieira's policy, including some of his appointments, had served in a military junta that toppled Vierira in the 1998-1999 civil war after his rule of 19 years. Vierira returned to power in the 2005 presidential election.

In the meantime, The African Union (AU) on Tuesday urged the authorities of Guinea-Bissau to launch a full investigation into the assassination of President Joao Bernardo Vieira and his chief of general staff, Batista Tagme Na Waie.

The AU Peace and Security Council "calls on the national authorities of Guinea-Bissau, in cooperation with the AU, ECOWAS (Economic Community of West African States) and other African institutions, to launch a full investigation into the president and the army chief of staff of Guinea-Bissau," said a communique issued after the 174th meeting of the AU Peace and Security Council.

Guinea-Bissau's parliamentary speaker Raimundo Pereira takes oath as the country's interim president March 3, 2009.[Xinhuanet.com]

However, during the talks, the pan-African body didn't decide to suspend Guinea-Bissau's membership, as were Mauritania and Guinea following coups last year.

The council requested the AU Commission, the executive arm of the pan-African body, "to submit to the council, within 30 days, a report on the situation in Guinea-Bissau, with recommendations for concrete action to be taken," said the communique.

(Xinhua News Agency March 4, 2009)