We have studied the sequence of events that occurs when a high-speed projectile (from 960 m s(-1) to 1480 m s(-1)) penetrates a vessel filled with toxic liquid. We find that prior to liquid ejection several well-defined phases occur, including the phenomenon known as the "hydraulic ram." Then a catastrophic tank failure leads to liquid ejection and fragmentation. This paper focuses on this phenomenon and explains how it can be related to the initial conditions of the target. (C) 2009 Elsevier B.V. All rights reserved.