Image copyright Getty Images Image caption Singer T.O.P. is not in a life-threatening condition, reports say

Korean singer T.O.P., one of the biggest stars in Asian music, is recovering in intensive care from a suspected drug overdose.

He was performing mandatory military service as a policeman when he was found unconscious at his station.

The 29-year-old is not in a life-threatening condition, reports say, but is unresponsive.

T.O.P., whose real name is Choi Seung-hyun, is a member of Bigbang, one of the world's most successful boy bands.

The group's top five videos on YouTube have a combined 935 million views.

"Choi's condition is very bad," one of his doctors told the AFP news agency.

The singer's medical team told the Korea Herald that the singer was suspected to have overdosed on benzodiazepine, a range of prescription tranquilisers used to treat anxiety, among other conditions.

Image copyright Getty Images Image caption Bigbang perform at the 2014 Asian Games in South Korea

"He was in a state of stupor and deep drowsiness and only responded to very strong stimulation," the newspaper said.

"He is still not breathing properly and is recovering. We are currently attempting to treat him but he's in an unresponsive state."

The newspaper said that another doctor believed the singer could recover in a week.

T.O.P. had been embroiled in a controversy over marijuana use before his hospitalisation. It is alleged he smoked marijuana on multiple occasions, even though the drug is illegal in South Korea.

As a result, he was transferred from his compulsory service posting at a police station in affluent Gangnam, where he had been serving for months, to another station.

He was found unconscious in the barracks of his new posting on Tuesday.

His entertainment agency, YG, released a statement apparently written by T.O.P. a few days previously.

"I deserve punishment for hurting the members, agency, public, fans and family," he said.

"I'll regret this for tens of thousands of years."