The first indication that the situation had changed significantly was on 23 June, when a group of 200 Ustaše clashed with a group of rebels they estimated to number between 600 and 1,000.
Reports of the uprising reached Kvaternik during 25 June, but he dismissed them and the reports of 5,000 rebels, cancelling Adriatic Command's redeployment of the 21st Battalion from Slavonski Brod as well as a request to the Italians for air reconnaissance support.