Bolivia’s rightwing interim government has turned up the heat on former president Evo Morales, accusing him of committing acts of terrorism and sedition by fanning street protests and blockades.

The country’s new interior minister, Arturo Murillo, announced on Friday that he had asked the public prosecutor’s office to open an investigation into Morales after the release of an audio recording supposedly showing the exiled leftist orchestrating plans for roadblocks designed to suffocate the country’s main city, La Paz.

Morales, who resigned under pressure from the military and protesters on 10 November, has described the recording as “fake”, but protests by his supporters have piled pressure on the interim president, Jeanine Áñez, a former senator.

On Friday a representative of Bolivia’s anti-drug trafficking council claimed drug money was being used to finance an “insurrection” against Bolivia’s new government – but offered no proof for the claim.

“Evo Morales is an international criminal,” Leonardo Roca claimed on national TV.

An editorial in the conservative newspaper Página Siete said on Friday: “No one doubts that Evo Morales has genuine support … but there is also ample evidence that the protests seeking to return him to power have degenerated into using violent methods.

“The most serious thing is that Evo Morales himself directs these protest from exile,” it added.

Two weeks after Morales fled the country, his followers have mobilized across the country, throwing up hundreds of roadblocks to prevent fuel and food reaching Bolivia’s de facto capital and thus force concessions – perhaps even Morales’s return.

The protests have already started to bite, causing shortages of food and fuel – and huge queues outside bread shops and petrol stations.

Authorities have been forced to mount an airlift, transporting some 1,400 tonnes of food to the besieged cities of La Paz, El Alto, Oruro and Sucre.

Bolivia has been in upheaval since Morales proclaimed himself the winner of a 20 October election despite widespread allegations of electoral fraud. Thirty-two people have been killed.

Morales alleges that he was the victim of a coup d’état and has been granted asylum in Mexico.

On Friday, Áñez pleaded with protesters to end a blockade at a natural gas plant that supplies La Paz.

“I ask for reflection from brothers who are carrying out this unnecessary blockade,” she said. “We’re all Bolivians. You can’t punish the city of La Paz.”

Eight people died in clashes with the military outside the gas plant on Tuesday. Two days later, thousands of Morales supporters carried the coffins of the dead into La Paz, where police fired teargas at them.

Áñez reiterated that she will only stay in power long enough for there to be new elections. But her critics say her cabinet have overstepped the bounds of a caretaker government by making changes to foreign policy and threatening to punish Morales’s allies.