Gunmen ambushed a buscarrying dozens of people in western Ethiopia near the Sudanese border, killingnine and wounding six others, Retuters quoted state-run media as saying onWednesday.The bus ambush on Tuesday evening - near the $4 billion-Grand Renaissance Dam -was the second attack on public transportation in the Benishangul Gumuz region infive months."The bus was targeted while travelling 100 kilometres (62 miles) south of (regionalcapital) Assosa," a report on state-owned Ethiopian Television said.