Pentagon Press Secretary George Little had insisted that the naval ship had issued several warnings to the fishing boat in the Persian Gulf before it fired shots that killed an Indian fisherman and injured three others.
US State Department spokesperson Patrick Ventrell, meanwhile, said the Department of Defence was conducting an investigation into the incident that has earlier been described as regrettable.
"... And we, of course, will work with our Indian counterparts and be as transparent as possible to provide them the results of our investigation
once it's finished," Ventrell said in response to a question. He said the Pentagon, which is probing the matter will be in touch with the Indian officials.
The incident happened on Monday when a small fishing boat carrying six people -- four Indians and two Emiratis was fired upon by a security team onboard the US Navy vessel.
External Affairs Minister S M Krishna termed the killing as "unfortunate" and said his ministry was in touch with its ambassador in UAE, M K Lokesh, who has raised the issue with the UAE government.
Lokesh, on his part, disputed American claims and said the survivors' account differs from that provided by the US Navy.
"According to the survivors, there were no warnings given to them," Lokesh told PTI in Dubai. "There are many versions of the incident. We have to wait for the details to emerge," the ambassador said.