IOTO, Japan - Dozens of aging U.S. veterans, many in their early 90s and some in wheelchairs, gathered on the tiny, barren island of Iwo Jima on Saturday to mark the 70th anniversary of one of the bloodiest and most iconic battles of World War II.

More than 30 veterans flown in from the U.S. island territory of Guam toured the black sand beaches where they invaded the deeply dug-in forces of the island's Japanese defenders in early 1945.

They were bused to the top of Mount Suribachi, an active volcano, where an Associated Press photo of the raising of the American flag while the battle was still raging became a potent symbol of hope and valor to a war-weary public back home that was growing increasingly disillusioned with the seemingly unending battle in the Pacific.

For some of the veterans, the return to the island where many of their comrades died, and which is still inhabited only by a contingent of Japanese military troops, brought out difficult emotions.

"I hated them," said former Sgt. John Roy Coltrane, 93, of Siler City, N.C. "For 40 years, I wouldn't even buy anything made in Japan. But now I drive a Honda."

Speeches at the Reunion of Honor ceremony held near the invasion beach were made by senior Japanese politicians and descendants of the few Japanese who survived the battle. Also speaking were U.S. Secretary of the Navy Ray Mabus and Gen. Joseph Dunford, the commandant of the Marine Corps, who noted that the battle for Iwo Jima remains the "very ethos" of the Marine Corps today.

"We should never forget that the peace and prosperity of Japan and the United States at present has been built on the sacrifice of precious lives," Japanese Defense Minister Gen Nakatani said in his remarks.

This was the first time that Japanese Cabinet officials attended the anniversary ceremony, now in its 16th year. And while the presence of veterans able to make the grueling trip has been steadily dwindling, the number of participants - about 500 - was double that of last year because of the significance of the 70th year since Japan's surrender ended World War II.

After the joint memorial, the U.S. and Japanese dignitaries and guests went their separate ways to visit the parts of the island that were of the most significance to their own troops. The Japanese have erected several memorials to their dead, and in a traditional way of placating their souls poured water and placed flowers on the memorial sites.

The Marines invaded Iwo Jima in February 1945, and it was only declared secured after more than a month of fighting. About 70,000 U.S. troops fought more than 20,000 Japanese - only 216 Japanese were captured as POWs and the rest are believed to have been either killed in action or to have taken their own lives.

The island was declared secure on March 16, 1945, but skirmishes continued. In about 36 days of battle, nearly 7,000 U.S. Marines were killed and 20,000 wounded.

It is to this day considered sacred ground to many Japanese. As a haunting reminder of the ferocity of the fighting, search teams continue to dig up more and more Japanese remains each year - it is estimated that 12,000 have yet to be found.

The United States returned the island to Japan in 1968. Wreckage of military equipment can still be seen dotting some of the beach areas, along with pill boxes and extensive mazes of caves.

Though the idea of developing the island for tourism has been mulled for decades, and possibly using its natural hot springs as an attraction, the island is virtually untouched other than the small airfield used by the Japanese.

Though a tiny volcanic crag, the island - now called Ioto or Iwoto on Japanese maps - was deemed strategically important because it was being used by the Japanese to launch air attacks on American bombers. After its capture, it was used by the U.S. as an emergency landing site for B-29s, which eventually made 2,900 emergency landings there that are estimated to have saved the lives of 24,000 airmen who would have otherwise had to crash at sea.

Twenty-seven Medals of Honor were awarded for action in the battle, more than any other in U.S. military history.

The only surviving Medal of Honor recipient from Iwo Jima, Hershel "Woody" Williams, 91, attended the ceremony. Afterward, he said his feelings toward the Japanese had not changed in the decades since the battle.

"They were just doing their jobs, just like we were," he said. "We tried to kill them before they could kill us. But that's war."