Rausan Ali Mondal, a mason by profession, slipped and fell into the 30-feet deep well at Eksara village in Howrah district.
Fire brigade and disaster management personnel were carrying out rescue work at the site, West Bengal Disaster Management Minister Javed Khan said in Kolkata.
There were no official reports on his condition even seven hours after his falling into the well as rescuers continue their search for him.
Asked about the fate of the youth, the minister said, "Our men are inside the well. Let them come out, then we can tell (you about the youth's fate)."
The Fire minister dismissed complaints of late response by fire brigade personnel and the disaster management team in reaching the spot after the incident that took place at about 1530 hours today.
"No it (late response) is not true. It is the creation of the media. The fire brigade personnel reached the spot within 15 to 20 minutes after the distress call was received from the Howrah district administration at 1635 hours," Khan told reporters.
"There had been heavy rain in the area which delayed the rescue operation. The well was very narrow and there was huge accumulation of methane gas inside," he said adding "our men are inside the well.