

A judge in Ecuador has jailed a Swedish software developer whom authorities believe is a key member of WikiLeaks and close to Julian Assange, while prosecutors investigate charging him with hacking as part of an alleged plot to “destabilise” the country’s government.

Ola Bini, 36, was ordered to held in preventive detention on Saturday pending possible cyber-attack charges and his bank accounts were frozen. Prosecutors were examining dozens of hard drives and other material he had in his possession, according to local media reports.

Bini was arrested at Quito’s international airport on Thursday as he was about to board a flight to Japan. Friends say Bini who describes himself as a “programming language nerd” on his twitter account is being unfairly targeted for his activism on digital privacy.

On Thursday, Ecuador’s interior minister, María Paula Romo, said they had identified a “key member of WikiLeaks” who was “close to Mr Julian Assange”.

Secret visitors’ logs seen by the Guardian show that Bini was one of Assange’s many visitors in Ecuador’s embassy in Knightsbridge, west London.

Others included senior staff members from the broadcaster Russia Today and celebrities such the designer Vivienne Westwood and the actor Pamela Anderson. A source who did not wish to be identified described Bini as a “personal friend” of Assange.

Bini paid a three-hour visit to Assange, leaving around 9pm in June 2016, just a week after the whistleblower received visits from RT’s London bureau chief, Nikolay Bogachikhin, who is Russian, and one of its presenters, Afshin Rattansi, a British citizen.

Last week, the government of president Lenín Moreno, 66, accused WikiLeaks of being involved in a campaign implicating Moreno and his family in corruption. Moreno, who has long expressed his unhappiness over Assange’s asylum status, complained that “photos of my bedroom, what I eat and how my wife and daughters and friends dance” had been circulating on social media.

Ecuador’s government believes WikiLeaks spread leaked documents, known as the INA Papers, which allege Moreno and his family had corruptly benefited from offshore companies when he was a United Nations special envoy on disability in Europe. Moreno denies any wrongdoing.

Bini, who has reportedly lived in Ecuador for several years, worked at the Quito-based Centre for Digital Autonomy focusing on privacy, security and cryptography issues, according to a blog under his name. It makes no reference to any link with WikiLeaks.

In a statement, the Centre for Digital Autonomy said: “People working for open source and privacy should not be criminalised,” noting Bini was a “world-renowned figure in the field of free software and defender of digital rights and privacy”.

On Friday, Bini was visited by the Swedish consul Ola Emberg, who told local media Bini seemed “sad and confused”.

Speaking to local media on Thursday, Romo said Ecuador was at risk of cyber attack, hinting Wikileaks could retaliate for the termination of Assange’s asylum. She added the government did not want the country “to turn into an international [cyber] piracy centre”.

The minister said two Russian “hackers” had been identified, telling local media later in the day: “We have sufficient evidence, this cannot be taken lightly.”

Romo also alleged Ricardo Patiño, the foreign minister who granted asylum to Assange in 2012, was involved in the “destabilisation” plot and had travelled with Bini to Peru, Spain and Venezuela.

Patiño denied any knowledge of Bini on Friday, tweeting: “The interior minister said the Swedish man that was arrested yesterday worked with me. I have never met him. Worse travelled with him.

“Nor do I know Russian hackers. The only Russians I know are: President Putin, the foreign minister Lavrov and the Russian ambassador,” he added.