Loyalty In Death by J. D. Robb
Eve Dallas has been chosen by a deadly revolutionary group, Cassandra, as their one true adversary. While investigating the seemingly simple case of a jealous lover killing her partner, she receives a disk from Cassandra, telling her to expect a demonstration of their power. Arriving just in time to see one of her billionaire husband Roarke's empty properties blown up, the link continues as more of Roarke's city landmarks are destroyed, testing Eve and her team to the limit and costing more and more lives.
Discovering that Cassandra is linked to a previous group, responsible for blowing up the Pentagon several years ago, things turn increasingly sinister as Eve realises that the murdered man and his family are implicated, and she races to break down the web of deceit and destruction before the city falls.