HANOI, Sept 28 (Reuters) - Vietnam weather authorities on Wednesday downgraded Typhoon Noru to a tropical storm, but warned residents of the risks from flooding and landslides caused by heavy rain, the government said in a statement.

The storm made landfall in the early hours with wind speeds of 117 km per hour (72 miles per hour) in the province of Quang Nam, home to the historic city of Hoi An and resort of Danang, the weather agency told state media.