The state broadcaster reports that the shooting has damaged the Government Palace and that ``invaders'' are holding government officials.

President Umaro Cissoko Embalo, a former army general, was believed to be inside the building at the time of the attack. He was declared the winner of the 2020 election, though the results were contested by Domingos Simoes Pereira.

Embalo then started forming a new government with support from the military while a Supreme Court election challenge was still pending.

Since gaining independence from Portugal in 1974, Guinea-Bissau has experienced four coup d'etats and more than a dozen attempted coups.

The small nation of around 1.5 million people, has long been beset by corruption and drug trafficking. In the 2000s, it became known as a transit point for cocaine between Latin America and Europe as traffickers profited from corruption and weak law enforcement.