China's first suicide intervention hotline alerted the public to "smiling depression" on Wednesday, which was World Suicide Prevention Day. The condition is hard to detect and can lead to suicide.

To date, the Beijing Psychological Assistance Hotline, set up in 2002 and run by Huilongguan Hospital, has received more than 210,000 calls, including more than 7,000 from people attempting suicide.

"But not everyone is lucky enough to escape from the hand of death," said Wang Cuiling, head of the hotline, citing a case typical of the so-called "smiling depression".