Six Sunni men who received death threats for meeting with local Shiites were killed on Saturday in execution-style slayings, police said. The attack near Youssifiyah, 20 km south of Baghdad, were apparently connected to rising sectarian violence that has included the claimed abduction and execution on Friday of at least 14 members of the Shiite-led security forces.Also on Saturday, the US military said it killed “key terrorists” who were using anti-aircraft artillery to fire at American military helicopters near Taji, north of Baghdad.The men gunned down—all relatives from the Mashhada tribe—-were killed after gunmen stormed the family’s house, police said.