The massive explosion at a fireworks market in Mexico was caught on video as it happened

A massive explosion ripped through Mexico’s best-known fireworks market outside its capital on Dec. 20, killing at least 29 and injuring a dozen people.

The blast struck San Pablito marketplace in Tultepec, north of Mexico City. A video captured by a passerby showed what initially appeared to be a huge, colorful fireworks show that quickly became engulfed by a plume of gray smoke.

Ten ambulances and 50 paramedics were sent by the Mexican Red Cross, a non-governmental organization said on Twitter. A video shared by the group showed people on the ground running as smog hovered above the market and explosions rang in the background. Reuters described the aftermath as a “charred wasteland.”

A lack of sufficient security measures had likely caused the blast, said Isidro Sanchez, the head of Tultepec emergency services.