University students and teachers staged a sit-in at the University of Baghdad to protest the detention of Iraqi scientists by US forces on suspicion of involvement in weapons of mass destruction programmes under Saddam Hussein. "My husband has been detained for 28 days in an unknown location," said Galshin, the wife of 49-year-old Ali Abdelraa al-Zaaq, who heads the university's faculty of genetics. "The Americans had already detained him from May to August and then released him, saying that he was not on the list of wanted scientists," she told AFP. "A month ago, he went to one of their bases to obtain a weapons permit and they arrested him again, arguing they had new evidence against him," Galshin said. "My husband has been detained in Abu Ghraib (prison) for six months without charges," said Sobhi aid al-Rawi, 59, who heads the computer science department at the women's faculty of science. "Some of the professors currently being held had already been interrogated once and had been very cooperative with the Americans," said Hoda al-Nuaimi, who heads the Centre for Palestinian Studies and was one of the sit-in's organisers. The 20-odd protestors waved banners which read: "Science is not a crime", "Release the scientists immediately". Asked about the arrests, US coalition spokesman Michael Pierson said: "Some scientists who were in the former regimes military are being held as prisoners of war." "Civilians who we detain whether they're scientists or not -- pose an imperative threat to security, either because of what they've done or what they know," he added. A large number of scientists who worked in the armament industry under Saddam's regime and are suspected of having taken part in a weapons of mass destruction programmes have since found jobs as university teachers. One scientist was murdered and another seriously wounded in shooting attacks in Baghdad shortly after they met with a team of US investigators last autumn. Many others have sought refuge in the United States since the end of the war. Saddam's alleged chemical and biological weapons caches were the main justification for the US-led military intervention in Iraq, but ten months after the end of major fighting, the coalition still has not found any weapons of mass destruction. **PHOTO CAPTION*** Iraqi students take part in a demonstration demanding the release of Iraqi scientists and academics held by the US-led forces at Baghdad's University. (AFP/Sabah Arar)