A massive 12 to 14 alarm fire broke out on Sunday afternoon, May 3, around 3 p.m. in Belleville, New Jersey, ripping through a mattress factory and spreading across multiple nearby industrial structures in a rapidly escalating blaze.

According to Mayor Michael Melham, welding activity may have caused the fire, although the incident is still under investigation.

📍 Belleville, New Jersey
🗓️ 5/3/2026

The gas and electric provider for the area cut power as a precaution, which left the Belleville Police Department without electricity during the emergency response. The township’s large school district, serving more than 5,000 students, was closed Monday due to the disruption and damage caused by the fire. Between 40 and 50 fire departments responded to the fire, with officials declaring a state of emergency as crews battled extreme conditions across the scene. Could THIA have prevented this fire? 

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To learn more about this thermal event, click the link below. 

https://nypost.com/2026/05/04/us-news/possible-cause-revealed-in-belleville-nj-warehouse-fire