The United Nations compound of high-rise buildings, green lawns and white SUVs has been an engine of prosperity not only for Africa's diplomatic capital but also for two senior managers, an internal U.N. report found. A December 2008 report by the now-disbanded U.N. Procurement Task Force says former officials Ventzislav Stoykov and Edgar Casals each scammed hundreds of thousands of dollars and ran outside ventures at the U.N.'s Economic Commission for Africa. The report obtained by The Associated Press says Stoykov manipulated bids and cut private deals with U.N. contractors he oversaw, while Casals forged birth certificates to get U.N. child support and used an American official to get U.S. visas for others _ a potential security risk. Both men have denied the allegations. As one of the last big investigations the anti-corruption task force completed before it was forced to shutter its operations at the end of 2008, the case illustrates the limits of the U.N.'s self-policing _ which has seriously eroded in the past year and a half _ and its secrecy and bureaucracy in handling major cases of fraud and corruption. «Investigations have been hampered and significantly slowed by the lack of cooperation of some parties, including vendors external to the organization, certain counsel for staff and vendors, and staff members themselves,» the task force says in its 131-page report. -- SPA