MEXICO CITY, June 6 (Xinhua) -- An explosion at a building used to store fireworks on Wednesday killed at least seven people and injured eight in the town of Tultepec, in the central State of Mexico, said local authorities.

The state government announced the explosion took place at around 1 a.m. in the neighborhood of La Piedad, located in the northern part of the metropolitan area of Valley of Mexico, known for its fireworks industry.

The statement said that seven people had died and eight more were being treated in hospital in the neighboring towns of Cuautitlan, Zumpango and Coacalco.

One woman and two men died at the scene in the explosion, and two more women died of their wounds while receiving treatment in hospital.

No details were given about the deaths of the final two victims, but the government said that four children, aged 7, 9, 15 and 16, were among the injured.

The explosion, which sent a big column of smoke billowing into the sky, had damaged 23 neighboring houses, five of them severely, and destroyed 12 vehicles.

"We are continuing efforts to attend to those affected, clean the area and search for ... more injured," read the statement.

The governor of the State of Mexico, Alfredo del Mazo, wrote on Twitter that he had appointed a team to attend to the injured and help the families of the victims.

This is the worst disaster seen in Tultepec since an explosion at a fireworks market killed 42 people in December 2016, which was kept closed for almost a year.

The town manufactures about 25 tons of fireworks a year in around 500 authorized workshops.

However, many locals also make and store fireworks illegally as authorities are launching campaigns to raise public awareness about the danger of this practice.