US immigration agents searched the home of Minnesota Representative Ilhan Omar on Monday morning as part of a “criminal investigation”.

Homeland Security Investigations (HSI) agents “executed a judicially authorized search warrant” for the home in the Washington, DC, area, a US justice department spokesperson told CBS News, the BBC’s US partner.

The search “is part of an ongoing federal criminal investigation,” the spokesperson said but no further details were given.

Omar was born in Somalia and came to the US aged eight fleeing war. First elected to Congress in 2018, she is running for reelection next month, and is an outspoken critic of President Donald Trump.

The US Congress is currently out of session and it is unclear if Omar was at the home. The BBC has contacted Omar for comment.

While the nature of the criminal investigation remains unclear, it is not the first time her immigration records have been scrutinised by Republicans. Earlier this year, fellow Congresswoman Nancy Mace of South Carolina unsuccessfully filed a subpoena of her records.

Omar, a Democrat, has been the target of Trump’s insults and the president previously suggested that she “should go back” to Somalia and at times said she should be deported. US citizenship is required to serve as a US House Representative.

Omar has responded to Trump’s insults and attacks describing them as “unhealthy and creepy obsession.”

The president has also spoken unfavourably about the Somali American community. Last week, he wrote on social media that Minnesota “is being taken over by Somali immigrants” and said “the people of Minnesota must fight back.”

Omar is the first Somali-American elected to the US House of Representatives and she represents a district in the Minneapolis area. She and Michigan Representative Rashida Tlaib were the first Muslim women elected to Congress.