* Family of Alek Sigley say he last made contact on Tuesday
* Friends report Australian man missing in North Korea - source
* Foreign Affairs Department seeking urgent clarification
* North Korea has detained other foreigners, including Americans
* Missing man is a student in North Korea (Recasts with statement from family, paragraphs 1-4, 19)
By Colin Packham
SYDNEY, June 27 (Reuters) - The family of an Australian student reportedly detained in North Korea said on Thursday they had not heard from him for several days and the Australian government said it was seeking urgent clarification on his whereabouts.
Alek Sigley's family said they had not heard from the 29-year-old university student in Pyongyang, the North Korean capital, since Tuesday, a spokeswoman for the family said in an emailed statement.
"He has not been in digital contact with friends or family since Tuesday morning Australian time, which is unusual for him," the spokeswoman, Lesley Parker, said.
Parker confirmed Sigley was missing but said his family had received no indication he had been detained in North Korea. Sigley was reported missing by friends, according to a source familiar with the situation.
Australia's foreign affairs department said it has received a report that a citizen had been detained in North Korea. The detention was first reported in South Korean and Australian media, which also identified Sigley.
"The Department of Foreign Affairs and Trade is providing consular assistance ... to the family of an Australian man who has been reported as being detained in North Korea," a spokesman for the Department of Foreign Affairs and Trade said in a statement.
"The department is urgently seeking clarification," he said.
North Korea's mission to the United Nations did not respond immediately to a request for comment.
FOREIGN PRISONERS
The treatment of foreign citizens, most usually from the United States, by the secretive North has been a contentious issue over the years. Some have been held as prisoners for extended periods. death of American student Otto Warmbier in 2017 after he was detained in North Korea for 17 months sparked a long period of tension between Washington and Pyongyang, with the United States and North Korea even trading threats of war.
Warmbier was detained in 2016 and sentenced to 15 years of forced labour for trying to steal a propaganda poster in his hotel. He was returned to the United States in a coma and died soon after. United States imposed a ban on its citizens travelling to North Korea in September 2017, with a few exceptions for humanitarian workers or journalists.
Those tensions were relieved somewhat by an historic meeting between U.S. President Donald Trump and North Korean leader Kim Jong Un in Singapore a year ago to discuss the North's nuclear and missiles programmes.
The problems remain unresolved, however, after a failed second summit in Hanoi this year.
Australia, a staunch ally of the United States, does not have a diplomatic presence in North Korea and relies on third-party countries to act on its behalf.
Australian Finance Minister Mathias Cormann said limited contact with North Korea meant securing details about the missing man's whereabouts was difficult.
"Our embassy in South Korea has reached out to relevant officials in North Korea," Cormann told Bloomberg Television.
"There is obviously some complications in providing consular assistance into North Korea. We work through the Swedish government in North Korea and all of these steps are underway," he said.
Sigley's family said he is a postgraduate student at Kim Il Sung University and had travelled to North Korea several times since 2012.
Sigley has written several articles for international media organisations about his time in North Korea, which he describes in positive language.
He regularly updates his social media accounts but has not posted anything on either Twitter or Instagram for several days.
The incident will likely dominate the agenda of Prime Minister Scott Morrison when he travels to Japan for the G20 summit from Friday. Morrison is expected to meet Trump during the trip to discuss, among other things, North Korea.