India agreed Wednesday to allow American military teams to search the Himalayan mountains for the remains of hundreds of U.S. service members who went missing during World War II.

“This is a humanitarian gesture by a government with whom we share so many values,” U.S. Defense Secretary Leon E. Panetta said in New Delhi at the end of a two-day visit. “The ability to return heroes to their loved ones is something that America deeply, deeply appreciates.”

During World War II, the Himalayas formed part of a major aerial supply route, a mission dubbed “flying over the Hump.” The route — which began at the eastern end of the Himalayas, wrapped over Burma and dropped into China — was dangerous because of cloud-knifing mountain peaks and bad weather.

Pilots flew the route to avoid Japanese-occupied Burma, and it was the Allies’ only option after the Japanese blocked the Burma Road. Several dozen U.S. planes crashed on those missions.

The families of the service members were told that the planes were lost over the Hump, but many did not know what that meant or exactly what had happened to their loved ones.

For more than six decades, the burned wreckage of the planes and human remains were left strewn across the remote Himalayan ranges. Now, teams from the U.S. Joint POW/MIA Accounting Command (JPAC) can search for the remains in India and bring them back to the United States.

This week, Vietnam also opened three sites for similar missions.

The renewed push for the recovery of troops’ remains can be partly attributed to the fiscal 2010 National Defense Authorization Act, which set high annual quotas for JPAC. But some Pentagon officials say such nonconfrontational work also helps extend the influence and reach of the American military in regions that are not historically friendly toward the United States.

The searches will not be the first in the Himalayan region. For years, an Arizona-based businessman, Clayton Kuhles, has journeyed up its steep slopes, crossed treacherous rivers and combed through dense jungles to find human remains as well as engine parts, identification plates, wing sections and other pieces of the planes. Kuhles has posted updates about his discoveries on his Web site,

Five years ago, a JPAC team went to verify a site where Kuhles reported finding the wreckage of a B-24 bomber known as “Hot as Hell.” The team began excavating the crash site but then abruptly left India. Some analysts say India did not want to upset China by allowing the Americans in the sensitive border regions of the state of Arunachal Pradesh that Beijing considers disputed.

“We have now indicated to the Americans that we would be understanding and sympathetic to this humanitarian work,” an Indian official said Wednesday on the condition of anonymity because he was not authorized to speak about the issue.

In an e-mail from Prescott, Ariz., Kuhles welcomed the announcement but expressed skepticism.

“It took JPAC eight years to identify and repatriate the remains I brought out from a C-87 crash site in 2003. The flight engineer from that aircraft was not returned to his family until April 2011,” he said. “It will take them many years just to recover the 20 sites which I have already found in northeast India. Time is of the essence in this project because many of the family members are quite elderly and are passing on.”