A US federal judge has ordered the son of a prominent Russian MP to remain in custody until his trial on computer hacking charges, after a prosecutor said evidence recovered from his laptop after his arrest in the Maldives gave new insights into the breadth of his activities.

Roman Seleznev, 30, the son of Russian MP Valery Seleznev, appeared in US district court in Seattle, where he was indicted in 2011 on charges that involved hacking into computerised cash registers, stealing hundreds of thousands of credit card numbers and selling the data online for at least $2m.

Seleznev faces similar but unrelated charges in Nevada.

In arguing for Seleznev to remain in custody, assistant US attorney Norman Barbosa told the court that at first look, his laptop contained 2.1m stolen credit card numbers, his criminal behaviour had not stopped and his profits had topped $17m.

“Those funds have remained beyond the reach of US law enforcement, so they are probably almost definitely available to the defendant” should he try to flee, Barbosa told magistrate judge James Donohue.

Even as Seleznev was on holiday in the Maldives he had been searching the online system of the US federal courts for charges filed against him under his own name and his online nicknames, Barbosa said.

The grand jury in Washington state indicted Seleznev on charges of bank fraud, obtaining information from a protected computer, aggravated identity theft, trafficking in unauthorised access devices and possessing stolen credit card numbers.

A month after the then-sealed indictment was returned, Seleznev suffered a brain injury in a terrorist bombing of a cafe in Morocco. He remained in a coma for two weeks and underwent a series of operations, said Robert Ray, one of his lawyers.

US secret service agents, working with local officials, arrested Seleznev at an airport in the Maldives last month as he was preparing to return to Russia from a holiday with his girlfriend. He was flown to the US territory of Guam, where another federal judge sent him to Seattle.

He has pleaded not guilty to the charges, which carry a range of potential penalties, with some counts punishable by up to 10 years in prison and a $250,000 fine.

The Russian foreign ministry has accused the US government of kidnapping Seleznev, and Ray reiterated that claim on Friday.

The prosecutor did not respond to that comment but said Seleznev had been careful to constrain his extensive international travel to countries that did not have an extradition treaty with the US. He noted that the arrest in the Maldives was made with help from local authorities despite the lack of an extradition treaty.

Ray suggested that his client should be released after posting $100,000 in cash on a $1m bond, and that he could be placed in home detention, with electronic monitoring and no internet access.

Ray conceded that the risk of escape was a valid concern for the court but said it could be overcome by those conditions, and that Seleznev posed no threat to public safety.

“He’s not going anywhere,” Ray said. “This case does not involve an act of terrorism. It does not involve an act of war.”

Even though Seleznev has surrendered his passport, “the court has no doubt he would be able to procure” documents that would enable him to escape, the judge said.

Andrey Yushmanov, Russia’s consul general in Seattle, attended the hearing and said the government remained concerned about the circumstances of Seleznev’s arrest. He said that if the US had a problem with the behaviour of one of its citizens, it should have contacted Russia. Instead, he said, the US turned to a third-party nation, as it did when it arrested Russian arms merchant Viktor Bout in Thailand in 2008.