CBS Los Angeles reports the explosion occurred in an LAPD truck located at East 27th and San Pedro streets at around 7:40 p.m.
The injured victims include nine LAPD officers, one Bureau of Alcohol, Tobacco, Firearms and Explosives officer and six civilians all being taken to the hospital, as well as a 10th officer who was hurt, but not hospitalized, the Los Angeles Fire Department confirmed to CBS Los Angeles.
The identities of the injured individuals were not made public immediately, but LAFD confirmed they include 11 men and five women who range in age between 42 and 85.
LAPD officials described the injuries as ranging from mild to moderate in nature during a news conference early Thursday (July 1) morning.
The planned detonation followed the seizure of more than 5,000 pounds of illegal fireworks from a home, which included the arrest of a 27-year-old man.
Ten pounds of the fireworks were placed in a specialized armored truck designed for controlled detonations, but the expected controlled detonation resulted in a massive explosion, which flipped cars and shattered windows within a two-block radius.
Police said it has yet to be determined how many homes were damaged in the accident.