Two people have been detained and a high-level investigation ordered into the explosion in Shivamogga district which left at least six dead, police said on Friday.
The detained included a contractor of a stone crushing facility where the blast occurred when a truckload of gelatin sticks went off, police added.
Karnataka Chief Minister B S Yediyurappa expressed grief over the loss of lives in the blast at the stone crusher facility at Hunasodu in Shivamogga, his home district.
A high-level investigation into the accident has been ordered and stringent action would be taken against the guilty, he said. He said he had been in contact with senior officials since last night and dispatched teams to carry out rescue operations.
"My deepest condolences to the bereaved family members. I wish a speedy recovery to the injured," the Chief Minister tweeted.
Meanwhile, the authorities have not ruled out the possibility of the death toll increasing.
"There are rumours that at least 10 to 15 people have died. Let the police complete their investigation," Shivamogga Deputy Commissioner K B Shivakumar told P T I on Friday.
The sound of the blast, which was initially thought to be an earthquake, was heard in neighbouring Davangere, Chikkamagaluru and Uttara Kannada districts.
In Shivamogga, the effect was severe as some houses developed cracks, roof tiles and window panes shattered into pieces.
The vehicle was badly mangled and the bodies of the victims were dismembered beyond recognition.
The toll has reportedly gone up to eight, according to multiple media reports.
The loud blast that occurred around 10.30 pm, resulted in the mild tremors in parts of Shivamogga, Chikkamagaluru, Uttara Kannada and Davanagere while causing considerable damage to buildings and civic infrastructure in Shivamogga city.
Sources in the Shivamogga district administration confirmed to DH about a high-intensity blast from dynamite sticks being brought in a truck to a quarrying site on the city's outskirts.
Sources at Hunasodu village where the powerful blast occurred said more than 50 dynamite and gelatin sticks were being carried in a truck.
Prime Minister Narendra Modi on Friday expressed pain at the loss of lives in an explosion in Karnataka's Shivamogga district and said the state government is providing all possible assistance to the affected.
In a message tweeted by the Prime Minister's Office, Modi said, "Pained by the loss of lives in Shivamogga. Condolences to the bereaved families. Praying that the injured recover soon. The State Government is providing all possible assistance to the affected."
Congress leader Rahul Gandhi also offered condolences to the families of the victims. "The news of blast at stone mining quarry in Karnataka is tragic. Condolences to the families of the victims. Such incidents call for in-depth investigation so that similar tragedies can be avoided in the future," he tweeted.
(With inputs from PTI)