In a call to dispatch ... a female can be heard on the line saying a man -- later identified as Cleveland Browns defensive lineman McDowell -- was "naked walking the premises" in Deerfield Beach, Fla.

The call is redacted, so it's unclear where the woman exactly is, but it seems she's calling from the school that cops say McDowell had walked near before his arrest on Monday afternoon.

"You're going to go into lockdown," the woman can be heard saying on the call. "You're going to have to take these kids into the bathroom, OK? Yes. One-by-one."

The woman then told dispatch McDowell was "out front."

"He's just walking up and down in front of the building," she added ... "He's completely naked."

At another point during the call, the woman can be heard again appearing to rush kids into lockdown, saying, "Whitney, help them get into their safe places!"

Two other callers, meanwhile, urged dispatch to get cops out to the scene ASAP ... describing McDowell as fully nude.

As we reported, cops say they were able to eventually tase McDowell at the scene and take him into custody. In video of the arrest, obtained by TMZ Sports, you can see McDowell was completely naked while interacting with cops.

McDowell was ultimately booked on charges of aggravated battery on an officer, resisting and exposing sex organs in public.

The Browns released a statement on the arrest on Tuesday, saying, "We are aware of the very concerning incident and arrest involving Malik McDowell and are in the process of gathering more information."

"We understand the severity of this matter and our thoughts are for the well-being of all involved. … No further comment at this time."