(CNN) - At least 18 officers fired their weapons during a shootout in Miramar, Broward County Police Union president Rod Skirvin said.
The deadly UPS truck hijacking unfolded in broad daylight on a major Florida highway on Thursday.
Thirteen of those officers were from the Miami-Dade Police Department, Skirvin said.
In addition to the two robbery suspects, bystander Richard Cutshaw and hostage UPS driver Frank Ordonez were shot and killed during the police shootout.
Investigators said Lamar Alexander and Ronnie Jerome Hill robbed a jewelry store, then hijacked a UPS truck to get away.
Police chased them on the interstate, and eventually a shootout occurred.
Authorities from multiple agencies are investigating the shooting.