The incident took place on Monday in Chamari village under Rengakhar police station limits and the exact cause of the explosion was not yet known, they said.
The impact of the explosion led to the collapse of walls and roof of the room where the music system was kept, the police said.
Rengakhar falls in a Naxal-affected area on Chhattisgarh-Madhya Pradesh border, around 200 km away from capital Raipur.
As per preliminary information, Hemendra Merawi (22) got married on April 1.
On Monday, he and the other family members were unwrapping the wedding presents inside a room in his house, Kabirdham Additional Superintendent of Police Manisha Thakur said. said.
As Merawi switched on the music system after connecting its wire to an electric board, an explosion occurred. Merawi died on the spot, she said.
His brother Rajkumar (30) and four others, including a one-and-a-half year boy, suffered injuries and they were shifted to the district hospital Kawradha, she said.
Merawi's brother succumbed during treatment. The others are undergoing treatment in the hospital, the police official said.
Soon after being alerted, a police team along with forensic experts went to the spot. The exact cause of the explosion is yet to be ascertained, she said.
Durgesh Rawte, station house officer of Rengakhar police station said during inspection of the room, no other inflammable item was found which could have triggered the explosion.
The music system was the only equipment which exploded in the room, he said, adding the cause of the explosion will be known after the investigation.
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