Security personnel have discovered a 70-metre-long tunnel dug by Naxalites in a dense forest along the border of Dantewada and Bijapur districts in Bastar division which is prima facie used as a bunker cum dumping place, a police officer said on Wednesday. According to police, they had received information about the existence of such an underground passage in the Bastar division in the past, but they have spotted it for the first time.

The tunnel, around 70 meters long and 6 feet deep, was spotted on Tuesday in the Bijapur district forest when a joint team of security personnel from Dantewada was conducting an anti-Naxal operation, Dantewada Additional Superintendent of Police, RK Barman, told PTI.

Personnel belonging to the District Reserve Guard, Bastar Fighters, both units of the state police, and CRPF's 230th battalion were involved in the operation, he said.

"During patrolling near Todopat-Uspari village, security personnel spotted the tunnel opening from a roof. Its openings were covered with long woods, bushes, and soil," he said.

According to Barman, this is the first such instance in the Bastar region wherein an underground tunnel has been discovered.

"Prima facie, Naxalites have dug this tunnel manually to use it as a bunker to hide from security personnel during operations in the area. They might have also been using it to dump Naxal-related materials," the police officer said.

However, details will be known after the investigation, he added.

"Police had received inputs about such a tunnel being dug by Naxals in forests under the Bastar region in the past, but it was spotted for the first time," another police official said.

Dantewada and Bijapur are among seven districts under the Bastar division.

Meanwhile, Barman said the anti-Naxal operation was launched based on inputs about the presence of cadres of the Bhairamgarh and Indravati area committees of Maoists in villages along the border of Dantewada and Bijapur districts.

He said a brief exchange of fire took place between security personnel and Naxalites, who lobbied shells of BGL (barrel grenade launchers). Naxalites soon fled the scene, he said.

On their way back, security personnel dismantled three Maoist memorials and recovered a cooker bomb planted in forests, Barman added.

Notably, three CRPF personnel, including two commandos of CoBRA unit, were killed and 15 others injured in an encounter with Naxalites along the border of Sukma and Bijapur districts on Tuesday.