Ilhan Omar

The nature of the investigation is unclear but comes after officials cast doubt on her US citizenship.

Omar, an outspoken Trump critic, said the search was "an attempt to target political enemies" and she "will not be silenced".

The BBC's Ione Wells reports from outside the Minnesota representative's home as several immigration agents were seen carrying boxes from the house to a van.

The Minnesota Democrat was uninjured and continued to speak at her event, after being sprayed with an unidentified liquid.

Two other members of the progressive group of Democrats lost primaries earlier this year.

Party members say it is due to past comments about Israel - but Democrats have called it revenge.

After a rare rebuke from colleagues, Democrat Ilhan Omar hits back at her critics' "tropes".