Iraq jihadis' newest tactic: Rent buildings, then wire them with explosives

“They change their methods periodically because most of their plans and tactics have been discovered. I believe they are already searching for another method of attack, maybe churches or bridges.”

Counter-terrorism expert Brian Fishman said of the HBIED operations: “The tactic is seen as very disreputable, even among active insurgents.”

But he added it allows them “to get around a lot of the tactics developed to prevent car bombs,” such as the mass of security checkpoints in Baghdad.