The Skype account of an Australian man who disappeared in North Korea is still active, providing hope for family and friends who fear for his safety.

Alek Sigley, a scholar studying and working in North Korea, has not been in contact with friends and family since Tuesday morning (AEST).

The New Daily can also reveal colleagues are concerned Mr Sigley could attract the attention of authorities because of potentially controversial books he took with him after his most recent visit to Australia.

Mr Sigley’s wife, Japan-based Yuka Morinaga, 26, told News Corp she last spoke to her husband on Monday night and did not notice anything out of place.

“We don’t know what’s happened. We don’t even know if he has been detained or not,” Ms Morinaga said.

“I’m worried, but we don’t know anything yet,” she said.

The student and tour guide usually has a highly visible social media presence, posting regularly about his life as the only Australian living in North Korea.

Mr Sigley has been positive about his experience and new friends there, and in March he wrote for Guardian Australia about his “invaluable insights” during his time at Kim Il-Sung University, adding he had “nearly unprecedented access to Pyongyang”.

“I’m free to wander around the city, without anyone accompanying me,” he wrote.

“Interaction with locals can be limited at times, but I can shop and dine almost anywhere I want.”

But on Wednesday he was suddenly – and inexplicably – silent.

In a statement, the Department of Foreign Affairs said it was “urgently seeking clarification” about the 29-year-old’s situation.

It’s understood checks are under way to determine if he has been detained and, if so, why.

The New Daily has confirmed Mr Sigley’s Skype account is mysteriously still on, despite him not being contactable by family and friends.

Australian National University’s Dr Leonid Petrov knows Mr Sigley personally and regularly communicates with him via messages.

“His Skype account is active. I tried to call him, but got no answer,” he said.

“I tried to talk to him via Skype … He’s not accepting telephone calls and messages.”

Dr Petrov said Mr Sigley lived in Australia with Ms Morinaga before he moved to the ‘Hermit Kingdom’.

Mr Sigley was passionate about building ties between North Korea and Australia and preparing to bring more tourists to the country before he went missing, Dr Petrov said.

“He was keen to bring more tourists. He speaks Korean, he’s trusted, he knows the market,” Dr Petrov said.

The New Daily understands Mr Sigley may have been in possession of politically sensitive materials he brought while visiting his home country in January.

During a trip home in March, where he visited his parents in Perth and gave a lecture to students at the University of Melbourne, Mr Sigley bought three revolutionary romance books written by Australian women.

Jean Devanny’s Sugar Heaven, Betty Collins’ The Copper Crucible and Dorothy Hewett’s Bobbin were the titles Mr Sigley took back into the country.

Sugar Heaven is about a woman who learns the “hard way about class and sexual politics in the heart of an industrial dispute over deadly Weil’s disease in the Cane”.

Mr Sigley is studying Korean literature and other academics say he was interested in comparing Korean and Australian texts.

North Korea remains one of the most heavily censored countries in the world, and the Supreme leader Kim Jong-un retains an absolute grip on the flow of information inside the country.

The rules of what people can take into the country are unclear but according to Young Pioneer Tours, which runs tours in North Korea, the only things completely restricted are bibles and pornography.

Could he suffer the same fate as Otto?

Many have drawn comparisons between Mr Sigley’s disappearance and Otto Warmbier, the American college student who was imprisoned in the country in 2016 after he stole a propaganda sign during an organised tour.

But his family stressed on Thursday afternoon that, while investigations were under way, they had no evidence to suggest Mr Sigley had been detained.

North Korean expert and lecturer at La Trobe University Dr Benjamin Habib said it was unlikely Mr Sigley had done something to offend the regime, as he would know the boundaries.

“In Otto’s case. he was a young dude who paid a big price for a mistake,” Dr Habib told The New Daily.

“In this case, Alek is not that person. It’s not like he’s a Christian missionary. He knows what he’s doing and he’s connected.”

If Mr Sigley has been arrested, it’s possible that he has got caught up in a power play between rivals within the government, he said.

“This is pure conjecture because we don’t know what’s happened but it’s possible he could have got caught up in internal power play that has nothing to do with him,” he said.

“At a wild guess, whoever his patrons are might have been purged or lost influence. So he’s got no backing.”

Originally from Perth, Mr Sigley is a former student at the Australian National University’s College of Asia and the Pacific, where he focused on North Korean propaganda. He graduated in July last year.