Construction of the Freedom Tower got underway Friday in New York City.
The tower is being built on the former World Trade Center site.
The search for human remains is not expected to interrupt construction.
Last month, the search for remains resumed, after bone fragments were found in an abandoned manhole.
Since then, more than 200 remains have been found.
Concrete on the Freedom Tower base was poured Friday and construction on the actual structure is expected to begin next month.