A freak accident killed a Brazilian policeman in the city of Belo Horizonte on Monday.

Thiago Ribeiro Trindade, 23, went into a car parts shop to buy a light. When he placed his backpack on the counter, it exploded and killed him.

"He put the bag on the counter where there were hot tools used for soldering. Contact with these produced the explosion," a police spokeswoman confirms.

The blast threw Trindade 6 feet, and injured three shop employees.

Authorities do not know what items in the backpack caused the explosion.