This paper considers controlled hybrid automata with forcible events. First, we introduce two semantics of the controlled hybrid automata using labeled transition systems. Next, we extend a concept of control-invariance in discrete event systems and show necessary and sufficient conditions for a predicate to be control-invariant. Finally, we show that there always exists the supremal control-invariant subpredicate for any predicate. (c) 2004 Elsevier Ltd. All rights reserved.