They were held at Chittagong airport on Wednesday just as they were about to fly out.
They said a syndicate of cheats had planned to send a total of 140 gullible people out of the country in batches of 70 in two different flights.
Twenty-one others have managed to give authorities the slip as they had already boarded the aircraft that flew them away before the RAB could stop them.
Only one of them had paid Tk 100,000 and another Tk 50,000, he said.
The rest were told to pay up after arrival.
He said they had plans to proceed to Italy from Libya either by themselves or through help from middlemen.
On their arrival in Libya, their families back home were harassed for money over phone.
Dhaka-Chittagong-Italy-Libya
An analysis of tickets reveals that their flight route would take them from Dhaka/Chittagong to Libya (Tripoli) via Dubai, Turkey (Istanbul/Ankara).
The 39 hail from a multitude of places ranging from Dhaka, Sunamganj, Sylhet, Habiganj, Munshiganj, Madaripur, Shariatpur, Barisal, Rajbari, Moulvibazar and Pabna districts.
They are supposed to loiter about at the 'Duty Free' shops at Dubai airport upon arrival and had been asked not to venture out of the airport, the RAB official said.
From there on, another group of the circle takes charge to send them to Libya via Turkey.
Once they arrive in Libya, two touts ‘Sadeque’ and ‘Muzammel’ detain them in several hotels of that country, the RAB has learnt.
One of those detained told bdnews24.com, "Frauds had told us that our flight from Turkey would depart at 5:20 on Thursday morning. He asked us not to venture out of the airport in the meanwhile."
Visa anomaly
Visas for 19 of them were issued on Oct 5.
All of these are tourist visas that expire in 30 days.
Two even carried visas that expired on Jun 10.
30 cheats identified
RAB has said it has managed to identify 30 of the members of the syndicate.
Two Sylhet travel agencies--Al Mamun and Shamim Tours and Travels have been found to have association with them.
RAB-7 Captain Miftah Uddin said all RAB offices have been alerted.
"We'll catch them wherever we find them," he said.