Seven hours of Donald Trump's telephone calls at the time of the deadly attack on the US Capitol have gone missing.
Internal White House records from January 6 last year have been turned over to the House select committee investigating the insurrection.
They have shown that Trump's phone logs of seven hours and 37 minutes, including the period when the Capitol was being violently stormed, do not exist.
All records from the White House are supposed to be stored.
Instead, 11 pages of the presidential diary, a record of the US leader's daily activities, and White House switchboard call logs show phone calls Trump had with at least eight people the morning of January 6 and 11 people that night.
However, all records turned over by the National Archives earlier this year to the House select committee from 11.17am to 6.54pm are missing.
The gap is in stark contrast to the extensive reporting on the day about phone conversations Trump had with allies during the attack.
Chairman of the committee, Bennie Thompson, called the reported gap in the log "concerning."
"Obviously, there is not a second in the day that the president of the United States is not on record somewhere," Thompson said.
He said the committee would see "if we can piece it together."
"Having a record of what the president was doing on that day is absolutely vital to the work of the committee," Thompson added.
The committee panel is now investigating whether Trump communicated on the day through backchannels, phones of aides or personal disposable phones, known as "burner phones".
In a statement, Trump said, "I have no idea what a burner phone is, to the best of my knowledge, I have never even heard the term."
However, his former national security adviser John Bolton has since said he recalls Trump using the term "burner phones" in several discussions, and the President was aware of its meaning.
Bolton said he and Trump have spoken about how people have used "burner phones" to avoid having their calls scrutinised.
A spokesperson for Trump said the former US leader had nothing to do with the records and had assumed all of his phone calls were recorded and preserved.
At least seven people died in connection with the insurrection, dozens more were injured, and hundreds of workers in the Capitol were shaken and left traumatised.
