US Capitol riot investigation: Was the attack planned?

As Senate Democrats in the United States gear up for Donald Trump’s second impeachment trial in a week’s time, the former President has until Tuesday to formally respond to the charge against him.

He is accused of inciting the deadly insurrection at the Capitol on January 6th.

Meanwhile, the investigation into the riot itself continues.

Scores of people have already been arrested in what is amounting to a probe of unparalleled scope.