Bolivia's attorney general said on Friday that his office has opened a probe into former President Evo Morales for alleged sedition and terrorism, related to accusations from the interim government that he has been stirring unrest since resigning.

The interior minister earlier filed a criminal complaint against the former socialist leader, based on evidence Morales described as fake.

Interim President Jeanine Anez, a former senator and opponent of Morales, has faced a wave of demonstrations by his supporters since taking office in a power vacuum last week.

Morales and his vice president stepped down under pressure from security forces and anti-government protesters on November 10, amid reports of irregularities in an October 20 election.

Morales fled to Mexico, which has granted him asylum, and says he was toppled in a coup. At least 29 people have been killed in clashes with security forces since he resigned.

Attorney General Juan Lanchipa said the foreign ministry would ask Mexico to allow Morales to provide his statement as a suspect in the investigation, which is based on a video Interior Minister Arturo Murillo distributed to media this week. In the video, a Bolivian man is shown talking to someone on a speakerphone who appears to be directing plans for road blockades.

Murillo said the voice on the speakerphone was that of Morales. 

Murillo told journalists outside the prosecutors' office in La Paz on Friday, "The evidence is clear. We've presented it."

Morales could not immediately be reached for comment. He said on Twitter that authorities should be investigating the deaths of protesters instead of going after him based on what he called made-up evidence.

Blocking roads is a common form of protest in Bolivia and much of South America. Intense blockades by Morales supporters have cut off fuel and food to some cities.

Authorities have transported some 1,400 tonnes of food by plane in less than a week due to blockades, the government said on Friday.