A bomb blast killed two American troops in Iraq, the military said Friday. The soldiers died Thursday when their Humvee hit a homemade bomb northeast of Habbiniyah in the Sunni Triangle. A third soldier was injured and hospitalized in stable condition, The AP reported. **Protests in Baghdad against constitutional law*** Meanwhile in Baghdad, thousands of Iraqis protested against a new interim constitution, while their religious leaders refrained from calling for a mass rebellion. "No, no to the basic law," the crowd chanted, waving banners that read: "We do not want an American constitution". For their part, Shiite clerics at weekly prayers also denounced the constitution, which was signed earlier this week. **Policemen arrested*** The attack came on a day when Iraqi police detained six police officers suspected of involvement in Tuesday's killing of two US government employees in Karbala. US investigators were looking into whether two US nationals and their interpreter were killed by Iraqi police officers or impostors in a carefully plotted assassination. The two employees of the occupation administration and their female interpreter were shot dead at a checkpoint by men in police uniform late on Tuesday night as they headed to their offices in Hilla, 100km south of Baghdad, from Karbala. **PHOTO CAPTION*** Paul Bremer, second from left, is escorted on his arrival at U.S. Army 82nd Airborne Division headquarters in Ramadi, 110 kilometers, 68 miles west of Baghdad, Iraq Thursday March 11, 2004. (AP Photo/Peter Andrews, Pool)