TEHRAN, March 11 (Xinhua) -- At least seven people were killed in the northwestern Iranian province of Ardabil in a blast of the homemade fireworks and explosives, Press TV reported on Saturday.
The explosion occurred in a residential building in a district in Ardabil a few days before the Chaharshanbe Suri, the Iranian festival of fire, Ardabil's chief prosecutor, Nasser Atabati, was quoted as saying.
The explosion happened due to the carelessness of a teenager while he was producing handmade fireworks and explosives inside the residential building.
Some materials used for the production of explosives were found beneath the rubble, Atabati said.
The teenager killed himself and six other family members, he said, adding that four others were injured, with one in a critical condition.
Chaharshanbe Suri is an Iranian festival celebrated on the eve of the last Wednesday before Iranian new year, or Nowruz. During the Chaharshanbe Suri celebrations, Iranians traditionally jump over bonfires and set off firework.
This year's Nowruz falls on March 21.