Saero walked in the kitchen to find Kami and Suna stabbed each by a machete.
Nigi, Sachi, and Mayuko ran in and the body announcement played.

Monokuma File:

Victims: Kami Hiro and Suna Sumida
Cause Of Death: Stabbed by a kitchen machete
Time Of Death: 1:00 am sharp
Place Of Death: Kitchen