WASHINGTON

The black box of a military helicopter involved in a deadly US mid-air collision earlier this week was recovered, the National Transportation Safety Board (NTSB) said Friday.

"The Sikorsky has a combined cockpit voice recorder and digital flight data receipt reporter. It's in one box.

"I can report to you now we have recovered the Sikorsky black box," NTSB member Todd Inman told reporters.

Inman said the black box is "safely" at NTSB headquarters.

A total of 67 people were killed after an Army Black Hawk helicopter collided with an American Airlines regional jet, near Ronald Reagan Washington National Airport, and plunged into the Potomac River late Wednesday.

"I can tell you from a visual inspection, we saw no exterior damage that would indicate that it was compromised at this time," said Inman.

The NTSB has a "high level of confidence" that it will be able to have a full extraction from that as well, he added.

'NTSB will not release manifest'

Iman stressed that the NTBS is conducting interviews with air traffic personnel.

"Air traffic control interviews are critical. That's the reason why there's a process in place that began immediately after the accident. It was preservation of that evidence," he added.

Turning to discussions about the manifest, Inman said the NTSB would not release it.

"I want to clarify one thing. There's been a lot of questions and discussion regarding manifest. Let me make this very clear, the NTSB will not and has not released a manifest

"We have not in our history, not in our past. We will not be in this accident," he said.

The NTSB will not be putting any names of any of the victims, he stressed.