Lawsuits are mounting over the mass shooting committed by Esteban Santiago-Ruiz at the Fort Lauderdale-Hollywood International Airport on Jan. 6, 2017.

Fort Lauderdale-based law firm Di Pietro Partners filed suit Thursday against Delta Air Lines, Broward County, the Broward County Sheriff’s Office and Allied Universal Corp., the parent company of AlliedBarton, the private contractor employed by Broward County to secure and protect the airport.