Rescue teams have now identified 55 of the 67 victims from last week's devastating American Airlines crash in the Potomac River, officials announced on Sunday evening.
The death toll has risen significantly from the previously reported 42 victims, as recovery efforts continue at the crash site near Reagan National Airport.
Crews are scheduled to begin a major lifting operation on Monday to remove wreckage from the river.
The recovered portions of the aircraft will be transported by flatbed trucks to a hangar for further investigation into America's deadliest aviation disaster since 2001.
Washington DC Fire and EMS Chief John Donnelly expressed confidence that crews would eventually recover the remains of the 12 still-unidentified victims
REUTERS
Washington DC Fire and EMS Chief John Donnelly expressed confidence that crews would eventually recover the remains of the 12 still-unidentified victims.
"If we knew where they were, though, we would already have taken them out," he said. "We have some work to do as this salvage operation goes on, and we will absolutely stay here and search until such point as we have everybody."
Col. Francis B Pera of the Army Corps of Engineers added: "Reuniting those lost in this tragic incident is really what keeps us all going."
Family members arrived at the crash site in 10 coach buses on Sunday, awaiting news about their loved ones.
More than 300 responders are working at the crash site at any given time, with two Navy salvage barges deployed to lift heavy wreckage.
The challenging recovery efforts saw a Metropolitan Police Department diver hospitalised with hypothermia, although he has since checked himself out and is "doing fine", according to Chief Donnelly.
An unnamed firefighter told reporters they were "emotionally wiped out after seeing the horror up close".
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The firefighter described the water as "actually very clear", saying that with their flashlights, rescue teams "saw horrible things when they arrived".
New details have emerged showing that the Black Hawk helicopter was flying hundreds of feet outside its approved route when the fatal collision occurred.
The military aircraft was meant to follow "Route 4" at Reagan National, which restricts helicopters to altitudes below 200 feet to avoid commercial aircraft.
However, sources revealed the Black Hawk was flying above 300 feet and at least a half-mile off its designated course when it struck Flight 5342.
An experienced air traffic controller noted that control tower instructions to the helicopter were "very ambiguous" in the moments leading up to the crash, as the Black Hawk failed to respond to a controller's request to "pass behind the CRJ" seconds before the fatal collision.
Sources have revealed that staffing levels at Reagan National's control tower were below normal standards at the time of the crash.
Only one controller was handling both commercial planes and helicopter traffic after another employee had been sent home.
Family members arrived at the crash site in 10 coach buses on Sunday, awaiting news about their loved ones
REUTERS
Although single-controller operations are standard practice after 9.30pm when traffic decreases, the crash occurred before 9pm.
A preliminary FAA report noted that the control tower staffing was "not normal for the time of day and volume of traffic".
The National Transportation Safety Board (NTSB), which is leading the investigation, will provide updates when available.
Transportation Secretary Sean Duffy raised key questions about the crash on television yesterday.
"What was happening inside the towers? Were they understaffed?" he asked on CNN.
"Staffing shortages for air traffic control has been a major problem for years and years," he said on Fox News, promising the Trump administration would address shortages with "bright, smart, brilliant people in towers controlling airspace".
The NTSB expects to release a preliminary report within 30 days, though full investigations typically take at least a year.
