Federal agents seized Democratic Rep. Ilhan Omar’s phone when they searched her Washington, D.C., home this week as part of a federal investigation into possible immigration-related crimes, and served about a dozen subpoenas in the case, according to two people familiar with the investigation. Possible charges cited by federal officials included conspiracy and making false statements in immigration proceedings, one of the people said. The search came just three weeks before the midterm elections, within the time period in which the Justice Department has typically avoided open actions in criminal cases that could affect an election. And the seizure of a sitting member of Congress’s phone would typically trigger a series of law enforcement protocols intended to ensure that investigators do not violate the “speech or debate” clause of the U.S. Constitution, which protects members of Congress from being questioned over their legislative acts. On Friday, about a dozen subpoenas were sent in the case, including to members of his family, the second person familiar with the investigation told NBC News. The congresswoman herself was not subpoenaed, the person said, adding that the warrants seeking information are tied to a federal grand jury in Minnesota, Omar’s home state. Federal agents also want to speak with Omar’s sister, but have not yet contacted her, the person said. The New York Times first reported on the subpoenas. The investigation is being led by Homeland Security Investigations, the U.S. attorney in Minneapolis and the Department of Justice. A spokesman for Omar did not respond to a request for comment. The Justice Department declined to comment. Omar said in a statement posted online Monday that she would not be silenced. “Make no mistake: this is an attempt to attack political enemies and weaponize federal authorities. For ten years, Trump has attacked me with baseless lies and smear campaigns. This is just the latest escalation in his campaign of political intimidation,” he wrote. One of the people familiar with the investigation said it involved complainants, documents and witness testimony. The investigation is examining issues related to Omar’s immigration status, including, but not limited to, his date of birth. Omar, who was born in Somalia and moved to the United States with his family in the 1990s, was naturalized when he was 17, meaning he was a minor and could be granted citizenship through one of his parents. A criminal investigation could be complicated by the statute of limitations, which is typically five years, but investigators could look into more recent actions by Omar or his family members that would fall within the statute of limitations. Omar, who is part of a group of progressive women in Congress known as “the Squad,” has been a frequent target of Trump’s rhetoric against her and other members’ liberal positions, as well as against Somali immigrants in general. Asked Monday if he had been aware of the search in advance, Trump said the federal government was watching Omar “very carefully.” He also repeated his frequent attacks against her and Somalia. “Then she comes here and complains about our Constitution,” Trump said. “I think he’s a terrible person, but that’s really up to the Department of Justice.” That night, Trump also attacked Omar in remarks at a rally he hosted for Republicans in Ohio. “I don’t know what they’re doing with it, but I can tell you this: It’s a disaster,” Trump said. “She comes from a country without laws, without police, without an army, where all they do is shoot each other, and she comes to our country and says: ‘I have a constitutional right.'” Homeland Security Secretary Markwayne Mullin appeared to provoke federal action against Omar last month when he said “something is going to happen” with her, but they were still investigating. “If we really move a case forward, it’s not a political case,” Mullin said. “It’s a real case because they did things wrong. If you decided to break the law or lie [about] the information you gave to the United States in order to enter the United States through asylum or because you simply wanted to seek a better life, but you did not tell us who you really were, you lied about certain things on your application; “Those things don’t expire.”