Karan received wounds on his neck and abdomen, police said.
Following a tip-off, two policemen conducted a raid at a Punjabi Bagh area park in west Delhi Tuesday night.
When the police enquired about his suspicious activities, Karan took out a knife and slashed his neck and abdomen.
Police said he was admitted to a government hospital where his condition was stated to be out of danger.
It is not known whether he is a history-sheeter. Further investigations were on