As a color-guard stood at attention, flag-draped cases containing the remains of the seven crew members of the space shuttle Columbia arrived Wednesday at Dover Air Force Base.

A C-141 military cargo plane carrying the remains from Barksdale Air Force Base in Louisiana touched down just before 2:40 p.m. at Dover, home of the military's largest mortuary.

Aboard the plane were seven coffin-like cases, symbolizing Columbia's seven crew members. Six cases were draped with American flags, the seventh with the flag of Israel in honor of Israeli astronaut Ilan Ramon.

Remains will be identified, primarily through DNA testing, and "released to their families as soon as possible," NASA Deputy Administrator Frederick Gregory said at a news conference.

Spokesman Bob Jacobs said Wednesday evening that NASA believes remains from each of the astronauts has been found. He added that Ramon's remains have been positively identified. He was unsure how that was done, but said NASA had forensic teams in the field.

"We're confident that we have seven sets of remains," he said.

After the plane taxied to a stop, Gregory and base commander Col. Scott E. Wuesthoff, accompanied by a chaplain and two honor guards, joined two rabbis who accompanied the flight from Louisiana.

The chaplain, Lt. Col. Karen Stocks, said a prayer before the remains were transferred to four white hearses and taken to the mortuary. On the tarmac, a color guard stood at attention as a stiff wind whipped the American and Israeli flags.

"We're basically a stop on the way home to the loved ones for these national heroes that perished," Wuesthoff said.

Workers at the mortuary will use DNA analysis and other techniques to identify the remains. "It could be days, it could be weeks, it could be months," mortuary director William Zwicharowski said.

The Dover mortuary also handled the bodies of the seven astronauts killed in the 1986 Challenger explosion and victims of the Sept. 11 terrorist attack on the Pentagon.