U.S. and British troops are reporting progress in Iraq as they move north from Kuwait toward Baghdad. Witnesses report bombs continued to fall on targets in the Iraqi capitol Saturday night.

More explosions are being heard after nightfall in Baghdad, following the first daytime air strikes of the war.

Thick smoke filled the air around the city after Iraq apparently set fire to oil-filled trenches surrounding the capital.

Warplanes, helicopters and tanks led the charge as troops fought their way near Basra, a city of more than one-million people.

U.S. Commander Tommy Franks says he has no plans for a major attack on Basra, because he says there does not appear to be a major concentration of Iraqi troops there.

Allied forces have taken a key bridge across the Euphrates River near An-Nasiriyah, about 375 kilometers southeast of Baghdad.

Thousands of Iraqi troops are surrendering, and defense officials say many others are refusing to fight.

A journalist traveling with U.S. forces in south-central Iraq reports that four soldiers were killed Saturday, although the Pentagon has not confirmed the information.