An Oklahoma city is not releasing a recording of the 911 call made from a Broken Arrow home where a couple and three of their children were stabbed to death.

Authorities initially said the call, described by Broken Arrow Police Sgt. Thomas Cooper as "gruesome," would be released Monday. An assistant to the city attorney indicated Tuesday that it wouldn't be released because it's part of the investigation into the deaths of the five members of the Bever family.

Robert Bever, 18, is accused in a booking document of five counts of first-degree murder and a count of aggravated assault in the attack Wednesday. Prosecutors say they also plan to charge Bever's 16-year-old brother as an adult.

Authorities believe the call was made by another brother before he was killed.