NORWALK - Norwalk fire and police officials found a stockpile of explosive chemicals this afternoon after an anonymous caller tipped them off.

Police were told at around 3 p.m. that a suspicious odor was coming out of the house at 25 Butler St. When they arrived, officers found between 50 and 70 gallons of highly explosive chemicals.

The chemicals were allegedly being used to make a gasoline additive to improve gas mileage. The man who owns the house, Guillermo Arteaga, rented it out to the suspect. He says that an odor developed as soon as the tenant moved in.

Arteaga says he had evicted the suspect, who was in the process of moving out when police arrived.