Mexico ministry denies bird flu case on US border 5 minutes ago MEXICO CITY (Reuters) - Mexico's agriculture ministry denied rumors in U.S. commodities markets on Thursday that a case of H5N1 bird flu had been found near the U.S. border. "We are free of highly pathogenic bird flu," Jose Angel del Valle, the ministry's animal health director, told Reuters. U.S. grain prices were lower early on Thursday amid talk of the deadly bird flu in neighboring Mexico, but livestock markets -- which stand to benefit -- were treating it as a hoax, traders said. The rumors apparently began on a Brazilian Web site, which reported that a duck found dead in the town of Nogales, near Arizona, had died of bird flu. The Western Hemisphere so far has had no confirmed cases of the deadly version of bird flu, which has killed more than 100 people in seven countries: Turkey, Iraq, Indonesia, Thailand, Vietnam, China and Cambodia. Mexican authorities killed some 300 birds after detecting low pathogenic bird flu on homesteads in the southern state of Chiapas last December. Del Valle said the agriculture ministry had a strict system of monitoring chicken farms and that other government bodies were closely watching wild bird populations for any sign of the virus.