An Australian filmmaker jailed for alleged espionage in Cambodia claimed he was arrested without a warrant yesterday, as he was hauled to court for questioning.

James Ricketson, 68, was arrested on June 3, a day after he was spotted flying a drone over an opposition election rally. He was held for almost a week before being charged with gathering information that could jeopardise Cambodia’s national security – a crime that carries a 10-year prison term.

“They arrested me without a warrant, and they do not allow me to meet my lawyer,” Ricketson told reporters at Phnom Penh Municipal Court, before prison guards blocked him from speaking further.

He was then questioned by Investigating Judge Pich Vicheathor for more than two hours, said Ricketson’s lawyer, Ou Helene. It was the first time she had been alongside her client at court, but she had met with him a few times in jail, she said.

The Interior Ministry and National Police have remained tight-lipped about the specific nature of his crime. However, an anonymous source told the Australian Broadcasting Corporation on Tuesday that Ricketson had been questioned about his links to former opposition leader Sam Rainsy.

Rainsy, who remains in self-imposed exile in France, yesterday denied any knowledge of a supposed documentary Ricketson was making about the former opposition president and the party.

“I am not aware of such a plan, if any. I haven’t seen the guy for years,” Rainsy said in the email. “But he remains a friend.”

A number of photographs depict Ricketson filming Rainsy at different events.

Prime Minister Hun Sen appeared to refer to Ricketson’s case on Monday, when he called for the arrest of “any spies in Cambodia”, whether foreigners or citizens.

“I condemn those who interfere in Cambodian’s internal affairs. Also, any spies in Cambodia have to be arrested for legal action regardless of nationality,” he said.

Ricketson has long been a critic of Hun Sen. In a Facebook post from 2013, he described the premier as the “Darth Vader” of Cambodian politics (with Rainsy being “Luke Skywalker”).

“Hun Sen’s style of government necessitates intimidation, the jailing of critics and opposition party members, tanks, razor wire barricades and a 10,000 strong personal body guard armed with state of the art weaponry,” he wrote, adding that Hun Sen was a “dictator in the Mugabe mold”.

Helene declined to comment on any opposition links and said Ricketson may be brought in for more questioning next week.