The Los Angeles County Sheriff’s Department admitted Tuesday that a private contractor did surveillance test flights over Compton for nine days in 2012.

The Sheriff’s Department said the goal was enhance public safety and impact criminal activity, but the news has frustrated many residents.

"That is a part of our liberty. Come on now. They took it away! You been spying on us?" former Compton Councilmember Barbara Calhoun said.

The Persistence Surveillance System flew aircraft equipped with cameras in the skies over Compton, but sheriffs say the images were "ineffective." The airborne cameras rolled for six hours a day in broad daylight.

"With respect to concerns about surveillance or being spied on as I know was being reported in the media, the footage that this high altitude camera that was on the bottom of the plane picked up would not make that possible," Capt. Leonard McCray said.

Due the ineffectiveness of the images, transmitters and monitors were removed from the courthouse and Sheriff’s station, and the department did not continue working with the contractor.

Some residents believe that they should have been told about the surveillance earlier.

"We might not be able to stop the experiment. But the people of the city of Compton and any city basically they have a right to know that this is at least going on," Jasmyne Cannick said.

Compton Mayor Aja Brown has asked the Sheriff’s Department for transparency and notification in the future.

"I do agree with the mayor, absolutely, that we should make sure that we do dialogue, and that that information is disseminated," McCray said. "If for no other reasons just to answer questions that may come up as we're answering now."

The Sheriff’s Department defends the use of cameras as a crime fighting tool. They said there are dozens in use at shopping areas and city parks throughout the city of Compton.