Togo's government says at least six top-flight soccer players have been killed and another 28 people are critically injured after a bus carrying them plunged into a ravine and caught fire.In a statement read on national television, the government said Togo president Faure Gnassingbe had ordered that the injured be taken to a military hospital in Lome, the capital.The accident happened Saturday near the city of Atakpame, about 99 miles north of Lome, as the Etoile Filante team was on its way to Sokode for Sunday's league game against Semassi.A tyre is believed to have burst, causing the bus to flip over and plunge down a ravine. Some of the victims reportedly burnt to death.