In the scene with the grenade, the bad guy initially picks up and holds a comparatively newer M26/M61 model grenade. In remaining shots of the same sequence, it suddenly becomes a WWII vintage MK2 "pineapple". (Spoiler here) Also, as Saiko is falling, palms open, her hands are clearly empty. Once she's lying down, she opens her hand and lets go of the grenade.