Unidentified 9/11 remains returned to 'Ground Zero'
Thousands of unidentified remains from the 9/11 attacks have been returned to "Ground Zero" in a solemn ceremony.
Fifteen vehicles took the remains from the Office of the Chief Medical Examiner to a repository under the World Trade Center site.
The move has split opinion among the families of victims, with some holding a protest at the memorial site.
The 11 September 2001 attacks killed almost 3,000 people in New York, the Washington DC area and Pennsylvania.
The remains consist of 7,930 fragments of human tissue that could not be identified by forensic teams.
They were placed in metallic boxes, covered in the American flag and taken in a convoy comprising fire trucks and police vehicles to the site of the attacks in downtown Manhattan.
Uniformed firemen and police then placed the boxes in a dedicated facility located underneath the 9/11 Memorial Museum.
The repository is 65 ft (20m) underground and will remain under the control of the Office of the New York Medical Examiner. Only family members and forensics teams will be allowed direct access.
Authorities say this will allow further identification attempts to be carried out if there are advances in forensic science.
Some family members held a silent protest at the site of the move, ending their vigil just before the transfer ceremony took place.
Sally Regenhard, the mother of a fireman who died in the attacks, told AFP that city authorities had not canvassed opinion among families because the majority were against the plan.
"The human remains of my son and all of the 3,000 victims should be in a beautiful and respectful memorial, not in the basement of a museum," she said.
"We are outraged. There is anger and anguish. It's an insult and a sacrilege," she added.
Rosaleen Tallon, whose brother was also killed, said: "Putting them in a museum is so hard to explain to my children."
However, the New York mayor's office said ahead of the ceremony that it would be "conducted in a dignified and respectful manner".
Other families also spoke out in support of the decision. Charles Wolf, who lost his wife Katherine, said: "I was proud when I saw the caskets with the American flag."
Of the 2,753 who died at the World Trade Centre, 1,115 have not been identified.
A new skyscraper, One World Trade Center, has been built on the site of the twin towers. It is now the tallest building in the western hemisphere.