The Los Angeles Police Department has reopened an investigation into whether members of the SWAT and Special Investigations Section units violated the law by purchasing firearms and reselling them for profit.
Chief Charlie Beck said that an earlier investigation, which found no wrongdoing on the part of officers, was "clearly lacking."
He acknowledged the second probe to the Los Angeles Times, which reported Friday that federal investigators were also investigating the matter. The newspaper cited sources who could not be named because they were not authorized to speak.
The probes stem from a whistle-blower lawsuit by a lieutenant who attempted to account for the LAPD Metropolitan Division's weapons in May 2010.
Lt. Armando Perez alleged he discovered that SWAT members had purchased an unknown number of custom-made pistols from the gun maker Kimber Manufacturing and were "possibly reselling these Kimber firearms for large profits to people outside of Metro SWAT," the lawsuit said.
A report by the LAPD's inspector general, Alex Bustamante, said as many as 324 pistols had been purchased from Kimber. The Times reports there are about 60 SWAT officers, and the guns were intended to be used by the officers while on duty.
Investigators have been trying to determine how many of those guns were resold and to whom.
Federal and state laws restrict gun sales by people not registered as weapons dealers.
The Times said the FBI was also looking into whether officers from the SIS, which conducts surveillance in major, high-risk cases, were also improperly reselling Kimber guns.
Andrea Ordin, president of the Police Commission, the department's watchdog, said the decision to alert federal authorities was probably made because they would be better qualified to assess whether any gun law had been violated.