Preliminary reports indicate no officers were injured, the Orlando Sentinel reported.
Leesburg police said they were searching for two to four men who fled into a residential neighborhood after firing on the undercover officers.
Leesburg police Capt. Robert Hicks said officers were confronted by "multiple suspects" and "words were exchanged" before the suspects opened fire. Officers returned fire and the gunmen fled in two cars. As police cruisers followed the cars through the neighborhood, two of the men jumped from one of them and and fled on foot, Hicks said.
The police captain did not say whether police located the second car and its occupants, the Sentinel reported
Hicks declined to say what type of undercover operation was in process. He did say police had conducted drug-bust operations in the area previously.
The Lake County Sheriff's Office is in charge of the shooting investigation because Leesburg officers were involved, officials said.