Children playing in a room stuffed with fireworks set off an explosion in a poor Sao Paulo neighborhood that leveled the house. Two children died and 13 people were injured, Brazilian media reported Sunday. Firefighters dug through the rubble of the home with the assistance of dogs for hours before finding the children - ages 4 and 5 - buried close to the area where their father was storing at least 10 boxes of fireworks, the Agencia Estado news agency said. Seven other people in the house suffered injuries after the explosion Saturday night, and six living in neighboring homes were hurt. Neighbors told Agencia Estado the children's father sometimes sold fireworks. Firefighters did not immediately return messages seeking comment.