FAO spokesman John Riddle in Rome told CBS Radio News, "When the FAO office opened this morning, an unidentified lone gunman injured and took hostage the FAO national and international staff in the building, about 40 people we believe."
Iraqi police and FAO officials said the gunman had walked into the building and opened fire in a downstairs reception area before going upstairs and continuing to shoot.
Two FAO staffers were killed and six people were seriously wounded, said Amir A. Khalil, director of FAO operations in Baghdad. He said the gunman held a U.N. consultant hostage at the FAO building's reception desk for over two hours.
Khalil said the other wounded included two U.N. staffers and four Iraqi government guards. A seventh casualty, a U.N. worker, was hurt trying to jump from a window of the U.N. Food and Agriculture Organization building, Khalil said in a statement.
"The dead and wounded remained in the corridor of the second floor for many hours," Khalil added. He identified the dead as Yusuf Abdilleh, an administrative officer from Somali and Marwewan Mohammed Hassan, a data base operator from Iraq.
The gunman, Fowad Hussein Haydar, denied shooting anybody in an unusual press conference given in a Baghdad police station hours after the event.
"I haven't shot anyone. When I left the building they told me two people were dead," Haydar said.
"True I fired at random. But the operation lasted more than two hours and there was heavy fire," he said, referring to the gunfire from Iraqi guards.
Haydar, 38, said his aim was to take Khalil hostage and then negotiate his demands.
"The reason is the embargo, the death and murder of thousands of Iraqi children and elderly. I wanted to relay a message, to explain the tragedy," he said.
Haydar said sanctions, which have impoverished millions of Iraqis, have driven him to the point of despair and warned that there are millions of people like him in the country ready to do the same.
The handcuffed Haydar appeared composed and peaceful. He stressed he was not recruited by any party to carry out his operation.
"I know I will be sentenced to death, but I am not sorry," he said.
In New York, the executive director of the U.N. Office of the Iraq Program, Benon Sevan, said the gunman first tried to enter the U.N. compound at the Canal Hotel and was turned away by security guards.
"Then he managed to enter the FAO offices in Baghdad and he took hostage about 50 people. He had two machine guns and made some demands," Sevan said.
"There were four demands, one being that there should be regular flights between Amman and Baghdad, the second being tha all allied airstrikes should stop and that there should be compensation for the victims of sanctions and the fourth being that there should be a monument erected before the U.N. headquarters for the Iraqi children," Sevan said.
Sevan said Iraqi forces "have been fully cooperative."
Khalil, the FAO representative, has been among the most outspoken critics of the effects of U.N. economic sanctions on ordinary Iraqis.
Khalil has pushed the sanctions committee to release holds on agricultural supplies like vaccines and irrigation equipment that he says are crucial to helping Iraq feed itself, but that members of the sanctions committee fear could have military uses. The United States has been the most active among sanctions committee members at blocking supplies to Iraq.
Sanctions imposed after Iraq's 1990 invasion of Kuwait have crippled the Iraq economy. According to U.N. resolutions, the embargo cannot be lifted until U.N. weapons inspectors report Iraq has destroyed its banned weapons of mass destruction.
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