The Rapid Action Battalion yesterday recovered a large cache of ammunition, including anti-tank rocket shells and chargers of launchers, from a bunker inside the Satchhari National Park in Chunarughat upazila of Habiganj.
The elite force also spotted six more underground bunkers there, but found nothing in those so far.
Investigations following the 2003 arms haul in Bogra revealed that the reserve forest, about 3km from the Indian state of Tripura, was used as a route by Indian separatist groups for smuggling arms.
However, Rab is yet to ascertain who stored the ammunition it recovered yesterday. Nobody was arrested in this connection as of last night.
Rab officials said they recovered 184 rocket shells (40mm) and 153 chargers abandoned in one bunker at the hillock of the reserve forest, some 130km off the capital, during the raid that started around 9:00am.
The crime-busting force also found some cleaning kits from the spot.
The ammos were wrapped in polythene and there was nothing written about the manufacturing country on the shells, said Col Ziaul Ahsan, additional director general (operations) of Rab, who took part in the drive.
"As they were wrapped in polythene the ammos look new," he told The Daily Star by phone.
Acting on a tip-off, Rab personnel had been conducting a special drive in the forest for the last few days, officials said.
Rab Media Wing Director Habibur Rahman flew there from Dhaka by a helicopter yesterday morning. He also took along with him at least four TV journalists.
The bunkers seem to have been built years ago.
Personnel from Rab headquarters and Rab-9 conducted the drive with the help of a dog squad and a bomb disposal unit.
"At one point of the drive, we found a hut made of hay. After digging several feet, a concrete slab appeared. Then we drilled a hole on the slab and found the bunker beneath the earth," Habib told this newspaper.
The drive was suspended at 5:00pm yesterday, but will resume this morning, report our Sylhet and Moulvibazar correspondents.
Locals said a clan of 20 to 25 Tripura families, the lone inhabitants inside the forest, live around half a kilometre from the place.
Sources in the law enforcement agencies said Indian separatist groups, including National Liberation Front of Tripura (NLFT) and All Tripura Tiger Force (ATTF), used the bordering forest area for shelter and as a training camp in the past.
On June 27, 2003, a truckload of ammunition was recovered in Bogra.
Investigators found links of NLFT and Ulfa (United Liberation Front of Asom) in that incident.
An investigator had told The Daily Star back then that the truck was loaded at Satchhari forest. He, however, could not say where the ammos were going.