Though some members of the crew were released later Bhavik Shah, who admitted to his crime, was detained for eight hours.
Later, Air India bailed him out by paying 5,000 pounds.
Confirming the incident, a senior Air India official said the cabin crew member has been suspended.
"We suspended crew member Bhavik Shah for the alleged incident on the same day when it was reported," an AI official told PTI.
According to airline sources, the incident took place last Friday after AI's Mumbai-London flight landed at the Heathrow airport.
While the crew members were on way to the hotel, the police carried out a search of their baggage.
During the search, there was no claimant for a bag which contained the 50 cigarette crates, following which the police detained the entire crew.
After a four-hour-long questioning, it was confirmed that the bag containing the cigarettes belonged to Shah, sources said.
Following this, Shah was detained for further questioning, and he admitted to carrying the contraband.
He was released on bail after AI paid up for the bond.
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