Gentlemen, I'm doing a spot of translation for a friend, and not being as well versed in warry things as most of you, I need some help. I'm listening to a French bloke talking about the GIGN, the Gendarmerie's Special Intervention Group, no probs there. But, when he's asked how they're used with regard to combatting the threat of terrorism in France, he says "well, they're used for classic surveillance operations, as well as stalking people of interest" Now that's the translation, I trust my French, but what would be a better word for "stalking" in this context? Any ideas? Thanks in advance.