Five people, including the ex-head of Mozambique's intelligence services and the chairman of three firms linked to the country's $2bn debt scandal, have been arrested in Mozambique, a police source said on Friday.

The source said those arrested also included the ex-private secretary to former president Armando Guebuza, and that some possessions, including luxury cars, had also been seized.

"Acting on the order of the attorney-general's office ... we made the arrests of five people," the police source told Reuters by phone, without giving the reason for the arrests. "I cannot give you further details," he said.

Antonio Carlos do Rosario, former director of Mozambique's intelligence unit, was arrested alongside Teofilo Nhangumele, the chair of state-run Proindicus, Ematum and Mozambique Asset Management, the police source said.

Reuters was not able to immediately contact the representatives of the individuals named by the source as being arrested.