Constable Raja Ram had shot himself on the night of July 27, a police officer said today.
Police said the reason behind the extreme step by was not known as no suicide note was recovered, but his family members have said he has been under a lot of stress and tension for the past few days.
Ram, a native of Haryana, had not disclosed the reason for his tension to his family, police said.
He was earlier posted at Indira Gandhi International Airport police station from where he was shifted to the Domestic Airport police station in April this year.
Earlier in January this year, a constable posted at Barakhamba police station had also committed suicide by shooting himself with his service weapon.