Soldiers patrolled the area around the presidential palace in Bissau, and a few people were seen walking along the main road leading to the building, where heavy gunfire rang out the previous day.

Military patrols combed through the capital overnight, according to AFP journalists.

A group of officers on Wednesday said they had seized "total control", suspending the electoral process as the country awaited the results of last Sunday's vote, which President Umaro Sissoco Embalo was expected to win.

Official provisional results had been expected on Thursday.

In the early afternoon, General Denis N'Canha, head of the presidential military office, told journalists that a command "composed of all branches of the armed forces" was assuming control of the country "until further notice".

He claimed a plan had been uncovered to destabilise Guinea-Bissau involving "drug lords", which had included "the introduction of weapons into the country to alter the constitutional order".

In addition to halting "the entire electoral process", he said military forces had suspended "all media programming", closed "land, air, and sea" borders, and imposed a mandatory curfew.

According to a military source, the head of this "High Command for the Restoration of Order" is expected to be announced on Thursday.

Sandwiched between Guinea and Senegal, Guinea-Bissau has experienced four coups since independence from Portugal in 1974, as well as multiple attempted coups.

The west African region has been rife with coups in recent years, with Mali, Burkina Faso, Niger and Guinea all seeing their governments toppled.