Jeremy Clarkson was suspended from the BBC after allegedly "aiming a punch" at a producer, according to reports.
The Radio Times reports the alleged incident involving a male producer took place last week, but was only reported to the BBC yesterday.
All three remaining episodes of Top Gear have reportedly been postponed while an investigation is launched.
Earlier, Clarkson, 54, took to Twitter to joke with co-stars Richard Hammond and James May about what programmes could fill Top Gear's usual slot on Sunday night.
ITV News has attempted to contact Jeremy Clarkson for his direct response to the allegations.
The BBC has given Jeremy Clarkson the all-clear to present Have I Got News For You, despite axing him from Top Gear over a recent "fracas".
Chris Evans has said rumours he will be taking over Top Gear are "absolutely nonsense."
Supporters of the suspended Top Gear presenter presented a petition signed by hundreds of thousands of people to the BBC today.