The Department of Justice on Friday issued about a dozen subpoenas in the ongoing investigation in the investigation into Rep. Ilhan Omar's immigration status. 

The congresswoman was not herself subpoenaed, but members of her family were, NBC News reported, citing unnamed sources. Investigators are trying to speak to Omar's sister, who was also not subpoenaed. 

The orders, according to the source, are tied to a federal grand jury in Minnesota, Omar's home state. 

The investigation is looking into matters related to Omar's immigration status. This includes her birthdate. Omar was born in Somalia and moved to the U.S. with her family in the 1990s. She was naturalized when she was 17 years old.