Do you have a link to this story? I'd have to call BS on the other rounds going off. Flash over occurs with black powder revolvers not with modern ammo. Even if the rounds had high primers the flat surface on the frame would seat the primers and not go off. You'd need something to dimple the primers to make them ignite. He probably got a round that was double charged either by accident or on purpose and the damage to either side of the chamber may have looked like they had gone off also. Over charged rounds can do a surprisingly amount of damage to a firearm.
USAF Retired, CATM, SC CWP, NH NR CWP, NRA Benefactor
To preserve liberty, it is essential that the whole body of people always possess arms, and be taught alike, especially when young, how to use them... -- Richard Henry Lee, 1787