Based on the results of optically detected magnetic resonance (ODMR) and time-resolved investigations we relate the observed lifetime shortening of intra-shell Mn2+ emission to spin dependent magnetic interactions between localized spins of Mn2+ ions and spins/magnetic moments of free carriers. We show that this mechanism is active both in bulk and in low dimensional structures, such as quantum wells (QWs), quantum dots (QDs) and nanostructures. (C) 2004 Elsevier B.V. All rights reserved.