The Oklahoma City Police Department placed officers on administrative leave after a prank tied to April Fools’ Day triggered what appeared to be a real emergency response that later proved to be false. The action followed reports and published police radio audio from the night of April 1, in which dispatchers relayed an account involving a child before later stating the call was not genuine, according to the Associated Press.

Police Capt. Valerie Littlejohn confirmed Monday that the department has an internal investigation under way. In a statement, Littlejohn said the department is aware of “a reported pursuit involving some of our officers that included serious claims, which has since been determined to be false,” and she said the agency is committed to a “thorough review” of the incident.

Littlejohn said she would not provide details about the accusations or say how many officers were placed on administrative leave. She said the department’s review followed published police radio audio in which dispatchers communicated information about the incident.

The reported audio included a dispatcher saying that “the city just advised that the suspect threw a baby out the window.” Another dispatcher can be heard saying that the officer in pursuit “does not have a radio” and instead was “just messaging his location,” the Associated Press reported, citing KFOR and other stations that aired the recording.

After multiple responders responded to the report, the audio later captures a dispatcher saying: “It was an April Fools’ prank.” In the same audio, a second dispatcher says, “Not funny,” the Associated Press reported.

The Associated Press also reported that a message left Monday with the president of the Oklahoma City police union seeking comment on the incident was not immediately returned.

The investigation comes amid state legal consequences for false calls. Oklahoma law makes it a misdemeanor to report “knowingly false information which could result in the dispatch of emergency services from any public agency,” with punishment that includes a fine of up to $500 and an assessment for any costs associated with dispatching emergency personnel.