US student Otto Warmbier medically-evacuated from North Korea in a coma as Dennis Rodman lands in Pyongyang

An American student being held prisoner in North Korea has been medically evacuated from the country in a coma, his family have said.

Otto Warmbier, 22, has been detained by the North Koreans for a year and a half.

He has been in a coma for more than a year, his family said, saying he had fallen ill shortly after his last public appearance during his trial in Pyongyang in March, 2016.

“Our son is coming home,” said Fred Warmbier, speaking to The Washington Post.

“At the moment, we’re just treating this like he’s been in an accident. We get to see our son Otto tonight.”

The Warmbiers were told that he had come down with a case of botulism soon after his trial – which lasted only one hour – and had been given a sleeping pill, from which he never woke up.

Rex Tillerson, the secretary of state, said that Mr Warmbier was on his way back to his home of Cincinnati, but did not discuss his medical condition.

The University of Virgina student was detained while "carrying out anti-DPRK hostile activities," North Korea's state media declared on January 22, 2016, using the country's official acronym.

They accused him of entering the country under the guise of a tourist and plotting to destroy North Korean unity with "the tacit connivance of the US government and under its manipulation."

"He is now under investigation," the report said, adding that he was detained on January 2.

In March he was sentenced to 15 years for taking down a sign of the Kim Jong-il, father of the current ruler, Kim Jong-un, while in the country with a tour group.

A China-based tour company, Young Pioneer Tours, which runs trips to North Korea, said at the time that one of its customers, "Otto" had been detained in the capital, Pyongyang.

He was on a New Year’s Eve tour in North Korea, en route to Hong Kong, where he was to do a January study-abroad trip.

But on his final night in Pyongyang - New Year’s Eve - Mr Warmbier appears to have gone to a staff-only floor of his hotel and attempted to take down a large propaganda sign lauding the regime.

His release came as basketball player Dennis Rodman - a self-proclaimed friend of Kim Jong-un - arrived in Pyongyang for his fifth visit to the country.

His visit, funded by an online marijuana sales company, was the latest stage in what the outlandish athlete terms "basketball diplomacy".

Asked by reporters in Beijing, during a connection to Pyongyang, why he was there, he replied: "To see if I can help."

It was unclear whether Mr Warmbier's release had anything to do with Rodman's arrival, and the state department denied his arrival was connected to Mr Warmbier's release.

North Korea holds a further three Americans - detaining several academics for offenses to the president.

The most recent two - Kim Hak-song, an employee of the Pyongyang University of Science and Technology, and Kim Sang-dok, an accounting instructor at the same university, were arrested last month in the space of a week.

When an American citizen is reported detained, the US works with the Swedish embassy in the North Korean capital, since the US and the North do not have diplomatic relations.

In total, 13 Americans have been detained by North Korea since 1995.