The Brazilian president Jair Bolsonaro has told a journalist he would like to “smash your face in” after being questioned over reports of a series of mystery payments into his wife’s bank account by a former police officer with alleged links to the Rio de Janeiro underworld.

Reports in the Brazilian media have claimed that between 2011 and 2017 at least 89,000 reais (about £12,000) were paid into the account of Brazil’s first lady, Michelle Bolsonaro.

The mystery deposits were allegedly made by Fabrício Queiroz, a longtime friend of Bolsonaro who was recently arrested as part of a corruption investigation into one of the president’s sons, and Queiroz’s wife, Marcia Aguiar. Flávio Bolsonaro and Queiroz have denied the corruption allegations.

Bolsonaro, who swept to power in 2018 vowing to stamp out corruption, has yet to adequately explain the payments and reacted peevishly when asked about them on Sunday.

“What I’d really like to do is smash your face in, yeah?” the far-right populist was filmed telling a reporter from one of Brazil’s leading newspapers, O Globo.

As he stood outside the Catholic Cathedral of Brasília, Bolsonaro then branded the journalist a safado (dirtbag).

His comments sparked immediate condemnation from members of the media and opposition politicians.

“This kind of behaviour not only demonstrates a lack of manners – it is also an attempt to intimidate the press and prevent awkward questioning,” the president of the Brazilian Press Association, Paulo Jeronimo told O Globo.

Within minutes of Bolsonaro’s remarks being reported, Brazilian journalists had launched a coordinated online campaign, repeatedly tweeting the very same question at their president. “President Jair Bolsonaro, why did your wife Michelle receive 89,000 reais from Fabrício Queiroz?” they asked.

There was no immediate response from Bolsonaro’s account, which has 6.6 million followers.

But by Sunday evening, the campaign had gone viral with some of Brazil’s most famous activists, academics and artists, including the legendary composer Caetano Veloso, joining the journalists’ chorus.

“We’ve got a playground bully in the presidential palace,” tweeted the left-wing politician Marcelo Freixo. “Why won’t he answer the question?”

Queiroz has known Bolsonaro since the 1980s and had reportedly also previously worked in the same police battalion as one of the most feared members of the Rio mafia: a notorious Brazilian hitman called Adriano da Nóbrega.

Nóbrega, allegedly one of the leaders of a gang of contract killers called the Escritório do Crime(Crime Bureau), was shot dead by police in February this year after going into hiding on a ranch in north-east Brazil.