LONGVIEW, Texas (AP) _ A tanker truck carrying 8,000 gallons of liquid propane exploded and burst into flames, forcing the evacuation of nearby homes and killing at least one. Another person was seriously injured and a third was missing.

A fire was still burning Monday morning, and police feared that a nearby propane tank holding as much as 30,000 gallons of fuel could also explode. Some 200 residents living within three miles of the Martin Resource Management Corp. yard in East Texas were out of their homes for a second day.

The tanker exploded Sunday as the 18-wheeler was transferring its load of propane. Witnesses said a line exploded, then the tanker truck caught fire and there was a second, larger blast.

``I thought it was thunder at first, and then I turned around and the truck exploded,'' said Dean Hensley, whose family owns 80 acres next to the plant. ``The two guys in between the truck and the storage tank were completely gone. They never got out.''

Gregg County Fire Marshal Jerry Pierce said it could take as long as 30 hours to burn off the fuel, and evacuees would not be allowed to return to their homes until then.

``The safest way to fight this _ and most environmental _ is to let it burn,'' Pierce said. ``There is no way to fight it until we know the cause and volume involved.''

The injured man, Martin employee Billy Davis, 57, was in serious condition Monday at Parkland hospital in Dallas.