Bolivia's interim President Jeanine Anez on Thursday accused former leader Evo Morales and his supporters of fomenting violence to try to force a return to power.
Socialist Morales, who currently lives in exile in Argentina, fired back, accusing the government of training its military to suppress social movements.
Conservative Anez assumed the presidency in November after Morales fled the country following three weeks of protests over his controversial re-election to an unconstitutional fourth term.
But she is under pressure to ratify a bill to set a new date for elections postponed over the coronavirus pandemic, which Congress passed despite her party abstaining.
"Evo and his coca growers are trying to return to power," said Anez, adding that Morales's Movement for Socialism party (MAS) is putting forward "the path of division and violence between Bolivians like they did during 14 years" of his rule.
The right-wing government has accused MAS of being behind the vandalism of telecommunications masts in rural areas by locals who believe a conspiracy theory that coronavirus can be spread through 5G.
Morales responded with a tweet claiming that two weeks ago a military document was circulating "with instructions to practice shooting and anti-terrorist preparation."
The former trade union leader described it as a "return to the US National Security Doctrine that views social movements as the 'enemy'."
Last week, both chambers of Congress approved a new date of September 6 for elections originally due to take place in May.
But on Tuesday, Anez proposed "postponing probably for a month or two months," citing an expected peak in coronavirus infections that is yet to be reached as reason to do so.
On Wednesday, Senate President Eva Copa, a member of MAS, urged Anez to "comply with the only mandate entrusted to" her by ratifying the election date.
When she came to power, Anez herself said her only role was to guide the South American country to new elections.
In the latest polls, Anez was sitting third behind former president Carlos Mesa and MAS candidate Luis Arce.
Bolivian interim President Jeanine Anez waves, while wearing a face mask, after attending a Corpus Christi procession at the Plaza de Armas in front of the government palace in La Paz, on June 11, 2020, amid the COVID-19 coronavirus pandemic