Two decades ago, Violeta Chamorro beat Daniel Ortega in Nicaraguan elections. This month, Ortega arrested Chamorro’s daughter as part of an unprecedented crackdown on opposition figures that aims to pave the way for his fourth consecutive presidential term.

The veteran strongman has picked off his targets one-by-one ahead of November’s vote. Since June 2, Ortega has arrested four presidential hopefuls, a senior businessman and two opposition leaders. An arrest warrant has also been issued for the president of the American Chamber of Commerce.

“It’s crystal clear he’s clearing the field to run without any meaningful opposition,” said José Miguel Vivanco, executive director of the Americas Division at advocacy group Human Rights Watch.

First in Ortega’s sights was Cristiana Chamorro, whose mother defeated the Sandinista rebel in elections in 1990. Accused of money laundering, which she denies, she has been held under house arrest.

Arturo Cruz, a former ambassador to the US, was next. He was detained on arrival at Managua airport under a treason law passed by Ortega late last year — one of a battery of repressive measures designed to neuter the opposition in the wake of protests in 2018, in which some 450 people died.

Then came Félix Madariaga and Juan Sebastián Chamorro, Cristiana’s cousin, both accused of inciting foreign interference in domestic affairs.

All four were potential candidates in November 7 elections in which Ortega, 75, who first took power after the Sandinista Revolution that overthrew the US-backed dictator Anastasio Somoza in 1979, is seeking another five-year term. He ruled from 1979-1990 and has been in power without interruption since 2007.

Violeta Granera, an opposition activist, José Pallais, a former foreign minister, José Adán Aguerri, former head of the biggest business lobby, Cosep, have also been detained. Amcham leader Mario Arana, a former central bank governor, is in hiding.

“Daniel Ortega is someone who would do anything to stay in power — there is no limit to the repression he would employ,” said Bianca Jagger, a Nicaraguan human rights defender.

One consultant, who asked not to be named in order to protect people he worked with in Nicaragua, called Ortega’s tactics a “piecemeal cancellation of the elections”. Or as Jagger put it: “What you’re seeing is a Daniel Ortega who will never go into an election that he will lose.”

Indeed, Ortega doubled down on control of the electoral apparatus in May, putting his FSLN party in charge of running the vote. He scrapped observers and enabled the barring of opposition parties.

Ortega’s increasingly brazen tactics are unlikely to spill over into protests because of widespread fear. Masked paramilitaries fired on demonstrators in 2018 and Ortega has tightened his grip on the country further since then. As one local put it: “He controls everything.”

Activists and regional political leaders hoped the US would step up. Nicaragua was included in what former US national security adviser John Bolton called the “troika of tyranny” alongside Cuba and Venezuela, yet “Ortega has enjoyed years of neglect from the US and the international community . . . therefore he has been able to get emboldened . . . without scrutiny,” said María Bozmoski at the Atlantic Council, a think-tank.

Despite US sanctions on allies and senior officials — including his wife Rosario Murillo, who is vice-president and mouthpiece of the regime, and some of his children — Ortega has thumbed his nose at Washington.

Cristiana Chamorro was detained while Antony Blinken, US secretary of state, was at a regional meeting in next-door Costa Rica. Others were arrested while Kamala Harris, vice-president, was in Mexico.

Still, “the only card left is the US”, said Laura Chinchilla, a former Costa Rican president. “Biden’s credibility is on the line.”

Julie Chung, acting assistant secretary for the Western Hemisphere, tweeted that “Nicaragua is becoming an international pariah and moving farther away from democracy”.

The US says it will reconsider Nicaragua’s trade access to the US if it fails to hold free and fair elections. But suspending it from the Cafta-DR free-trade pact could backfire.

“Keeping Nicaragua in Cafta is like injecting a dying patient with blood and keeping him on oxygen,” said Bozmoski. But if Nicaragua were suspended “the people who would suffer are the half a million whose jobs depend on the [export-oriented] free zone. Those jobs would seek to exist”.

Chinchilla urged lenders to “turn off the taps” while Vivanco appealed for “an avalanche of targeted sanctions against key officials” to turn up the heat on the Ortega regime.

But one veteran US diplomat said that even if that worked, it risked “further impoverishing a region where we are trying to do something” and could trigger yet more migration from Central America.

More than 100,000 Nicaraguans fled to Costa Rica during the 2018 protests, but the numbers arriving at the US border, while still low, had recently ticked up slightly, the diplomat added.

Ortega’s control over the country, including the army and police, give him protection, but the situation remains volatile.

“I’m not quite sure what’s going to happen,” said the consultant. “But I’m sure it’s not over.”

This article has been corrected to make clear that Daniel Ortega ruled from 1979-1990 after he overthrew Anastasio Somoza.