Capitol riot 'inspiration for extremism', FBI boss warns

The number of US homegrown terror cases has risen sharply, the FBI boss has said, as he warned that the deadly January Capitol riot may serve as 'inspiration' for extremists.

Some 2,000 FBI domestic terror probes are open, up from 1,400 at the end of 2020, Director Christopher Wray said.

Arrests of "racially motivated violent extremists," including white supremacists, have tripled since 2017.

For the first time, Mr Wray called the Capitol siege "domestic terrorism".

The attack could be "inspiration to a number of terrorist extremists," he told a Senate hearing on Tuesday.

Over 260 people have been arrested in connection with the storming of the US Capitol to date.