Calcutta airport customs found a dozen gold bars worth Rs 1.62 crore in an abandoned plastic bag at early on Wednesday.

A customs official noticed the “unattended bag” containing 5.87kg of gold at the ground- floor arrival lounge of the integrated terminal’s international wing before the customs check area around 1 am.

“Someone had brought the gold bars from abroad but dumped them at the arrival lounge out of fear of getting caught at the customs check,” an official said on Thursday.

He said a flight from Bangkok had landed minutes before the plastic bag was found. “It’s possible that the passenger came by that flight.”

The officials are trying to find out the owner of the bag.

They said gold smuggling has increased following a hike in import duty in August 2013.

A passenger has to pay 10 per cent of the value as customs duty and 3 per cent as cess, which works out to almost Rs 3 lakh a kilo. Earlier, the import duty on gold was Rs 22,000 a kilo.

The airport’s biggest haul so far has been 12 gold bars, weighing around 24kg and worth Rs 7.36 crore, found hidden in two washrooms of a Jet Airways aircraft on November 19 last year.

Airport officials said several passengers had been caught over the past few months bringing gold concealed inside LCD/LED TVs, torches and even in rectums.

“After the import duty was raised, vigilance has been stepped up too. This has scared some of the gold carriers,” an official said.