By Alex DeMetrick

BALTIMORE (WJZ) — Covert operations. The FBI flying planes over the Baltimore riots. Now new information is surfacing about the high tech tools the FBI was using.

Alex DeMetrick with details on how this new information came to light.

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Maryland’s ACLU secured the documents from the FBI and the FAA.

Not all of the eyes looking down on last spring’s riot and protests were news choppers and police helicopters. The website Flight Radar 24 picked up two planes circling far higher–planes being secretly flown by the FBI.

When FBI Director James Comey was questioned by Congress:

“It’s useful to everybody–civilians and law enforcement–to have a view of what’s going on,” said Comey.

“I think bland assurances from government officials simply don’t cut it,” said David Rocah, Maryland ACLU.

So Maryland’s ACLU pressed for FBI documents and found the aircraft have not only thermal imaging commonly used by law enforcement, the FBI’s can see through walls.

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The documents show most FBI flights were at night–from April 29 to May 3–totaling over 36 hours. Video surveillance occurred during half of those flights, and some kind of electric surveillance was done–but what kind? The FBI won’t say.

Also secret:

“Who it was being used on, how it was being used and what was done with the records?” said Rocah.

“We don’t fly around America looking down trying to figure out if somebody might be doing something wrong. The overwhelming use of our aircraft is a pilot flies as part of an investigation to help us follow a spy, a terrorist or a criminal,” said Comey.

“There just aren’t that many terrorism and spy investigations happening,” said Rocah.

Not with the thousands of flights the ACLU says are being made over American cities.

The FBI documents also reveal half of the flights over Baltimore carried a Baltimore City police representative.

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The ACLU says there are times surveillance is necessary for public safety, but new technologies require new rules to be used.