Investigations are underway into Wednesday night's tragic and fatal mid-air collision of a commercial passenger jet and a U.S. Army helicopter near Reagan National Airport in Washington D.C. that sent both aircraft plunging into the icy Potomac River.

Sources suggest one possible cause for the crash could be an understaffed air traffic control tower, as one of the two controllers who were supposed to be on duty at the time of the incident was reportedly sent home early, according to the Independent.

Other sources have also separately revealed that the helicopter may have been at fault for the collision as well, as it was reportedly flying both higher than and outside of its narrowly permitted flight path near the airport.

Understaffed air traffic control tower

On Friday, an NBC News reporter disclosed that he'd learned from anonymous sources familiar with the ongoing investigation that only one of two air traffic controllers who were supposed to be in the tower was actually on duty at the time of the mid-air collision around 9 pm on Wednesday.

Typically, one controller directs airplane traffic to and from the airport while the other directs helicopter traffic until at least 9:30, when traffic usually decreases substantially, but the supervisor that night allowed one of the controllers to leave early and combined the duties of both with the one remaining controller.

That seemingly confirms a report from The New York Times about the purported preliminary findings of the Federal Aviation Administration's ongoing probe that discovered only one air traffic controller was in the tower monitoring all traffic when there should have been at least two controllers working at that time.

In fact, the FAA preliminary report was said to have asserted that the understaffed tower was "not normal for the time of day and volume of traffic" that fills the busy airspace around Washington D.C.

Helicopter was flying off course

Meanwhile, The Times reported separately that multiple unnamed sources have revealed that the U.S. Army Black Hawk helicopter was likely flying higher than and outside of its approved flight path when the mid-air collision with the passenger jet occurred.

Typically, military helicopters are authorized to fly along a predetermined route past the airport that limits the aircraft to fly no higher than 200 feet along the east bank of the Potomac, which keeps them clear of the flight paths of commercial jets taking off and landing from the busy airport.

However, sources indicate that the helicopter was flying at an altitude higher than 300 and approximately a half-mile to the west of its approved route, which caused its path to intersect that of the passenger jet that was on its approach for landing.

The sources further indicated that the helicopter was warned by air traffic control at least once that it was off its authorized course as well as that the helicopter's crew would have been fully aware of the preset route and altitude restrictions they were supposed to adhere to.

Were Trump's initial reactions correct?

These media reports also appear to confirm at least some of what President Donald Trump was criticized harshly for proclaiming about the accident, including a Friday morning Truth Social post in which he stated, "The Blackhawk helicopter was flying too high, by a lot. It was far above the 200 foot limit. That’s not really too complicated to understand, is it???"

Trump also drew heat for appearing to suggest in his initial Wednesday night reaction and his Thursday morning press conference that the passenger jet had done everything it was supposed to do and that fault for the crash likely lay with the helicopter and the air traffic control tower.

Of course, we will have to wait for official confirmation on the veracity of these anonymously sourced media reports, but if they turn out to be correct, it would seem to suggest that Trump's intuition was right about who was responsible for the tragic incident that claimed 67 total lives.