Acting on tips from community members, detectives conducted a monthlong investigation and made both misdemeanor and felony fireworks-related arrests beginning in June and ending Friday, said Sgt. Rudy Gatto of the Irwindale Police Department.
The recovered fireworks were "appropriately destroyed" by authorities, Gatto said.
Photos released by the Police Department show a massive cache of fireworks, some in brightly colored packaging, others in plain cardboard boxes.
The contraband seizure comes days after the Los Angeles Police Department confiscated about 5,000 pounds of illegal fireworks in South L.A. That operation led to a detonation that resulted in "catastrophic failure," leaving 17 people injured.
South LA explosion: Illegal fireworks suspect released on bond
Anyone with information about persons possessing or selling dangerous fireworks is asked to make an anonymous report to lacrimestoppers.org or call (800) 222-TIPS (8477).
Tipsters may be eligible for a reward of up to $1,000 from Los Angeles Crime Stoppers.