Perhaps done in by the heat, a few of his tailcoat buttons fell to the floor.
The tailcoat opened up to reveal something like clay strapped to his stomach.
Mugino immediately realized what that clay was.

[…]

It did not even take a full second.
A tremendous explosion assaulted Item as it filled that corner of the floor.

[…]

“I told you your bomber man failed, didn’t I? Kinuhata and I tore the bombs from him and threw them away. Thanks to that, no one died and you didn’t get what you wanted.”

Toaru Majutsu no Index New Testament vol. 12 ch.3 pt.6