The media were not allowed to cover the somber ceremony at Dover Air Force Base on Tuesday when the remains of 38 U.S. and Afghan troops killed in a weekend helicopter crash arrived and were honored by President Barack Obama, despite appeals from news organizations.

Under a process spelled out in a 2009 policy approved by then-Defense Secretary Robert Gates, the decision on media coverage is left solely up to the families of the fallen. The Pentagon said Tuesday that 19 of the 30 families of the U.S. dead had objected to media coverage.

That followed initial conflicting statements about family notification and response. Initially, Pentagon officials said they had unilaterally prohibited media coverage in this case, because the badly damaged remains were mingled, making it impossible to individually identify each of the war dead at this point.

They later said that families were asked whether they would approve media coverage and some consented. But Pentagon officials argued that none of the families could give their individual permission for media coverage because the exact contents of each casket were unclear. In the end, 19 of the 30 U.S. families objected to media coverage, the Pentagon said.

Obama arrived at Dover to pay his respects and meet with the families of the U.S. forces whose remains were brought there aboard two military cargo planes. Members of the media covering the unscheduled trip had to agree in advance not to report on the trip until he had landed. The White House said the secrecy was to ensure the security of the president's helicopter flight to Delaware.

The military calls the process of moving the remains of fallen soldiers a dignified transfer. Cases draped in American flags are carried off a giant plane, one by one, by a team of military personnel. Each case is placed in a vehicle and then taken to a mortuary.

The 30 U.S. troops and eight Afghans were killed when their helicopter was struck by a rocket-propelled grenade. It was the single deadliest loss for U.S. forces in the decade-long war. The helicopter crashed and burned.

"Because the remains are unidentified at this point, next-of-kin are not in a position to grant approval for media access to the dignified transfer," Pentagon spokeswoman Capt. Jane Campbell said in an emailed statement to reporters Monday. "Therefore, in accordance with DoD policy, no media coverage of the arrival and dignified transfer is permitted. "

The Associated Press and some other news organizations protested that original decision, seeking clarification that the service members' families had been consulted in line with the military's policy, and also seeking access to the ceremony without showing the remains in transfer cases. Military and civilian officials attended the ceremony, along with Obama and family members.

In at least one previous case of mixed remains, The Associated Press in June 2010 was allowed to document an arrival at Dover because all three families of those who had died had agreed to media coverage.

The AP has covered every ceremony in which family have agreed to coverage, a total of 68 ceremonies this year at Dover through June 30.

Under the Pentagon policy spelled out in March 2009, the option to allow media access is explained to the family when they are notified of their loved one's death, and "primary next of kin will make the family decision regarding media access to dignified transfers at Dover."