U.S. investigators have hastened the search for missing pieces of the space shuttle Columbia as the first truckload of debris arrives at a Louisiana airbase to be analyzed.
Officials are racing against expected heavy rain that could make the search more difficult. They say each piece of debris is important in unraveling the mystery behind what caused the shuttle to break up as it entered Earth's atmosphere Saturday.
Remains of the seven astronauts killed in the disaster are being examined at a U.S. military mortuary in (the state of) Delaware before being returned to their families.
(The U.S. space agency) NASA expressed doubt Wednesday that a piece of foam insulation that broke from the shuttle's fuel tank during lift-off led to its disintegration. A top NASA official says investigators are still looking for a "missing link" in the chain of events that led to the disaster.
Meanwhile, two people in (the U.S state of) Texas have been arrested for allegedly stealing shuttle debris. The two (43-year-old Merrie Hipp and 23-year-old Justin Gaudet) each face up to ten years in prison and $250,000 in fines.