Ilhan Omar joins calls for independent investigation into former Egypt president Morsi's death
Morsi, Egypt’s first democratically elected president, died in an Egyptian courtroom on Monday.
He was being tried for charges including "contacting Hamas and Hezbollah" which were widely seen as trumped-up and politicised.
The 67-year-old former leader had been in prison ever since being ousted in a military coup in 2013.
He was held in solitary confinement and had been suffering from diabetes, hypertension, and liver disease.
In March this year, a panel of British MPs warned that Morsi could die prematurely if he was not given access to proper medical treatment for his illnesses.
After he collapsed in court on Monday, eyewitnesses said that he was left "slumped on the floor" for 20 minutes without help.
Omar, who came to the US as a refugee from Somalia and was elected to Congress in November 2018, has previously spoken out about human rights abuses in Egypt.
In in March she wrote "Our criticisms of oppression and regional instability caused by Iran are not legitimate if we do not hold Egypt, the United Arab Emirates and Bahrain to the same standards."
Last April, Omar demanded that Egypt release Huda Abdulmonem, a human rights lawyer who was arrested along with 18 other human rights activists in a crackdown by the Sisi government in November 2018.
Omar's outspokenness has made her a target for Saudi media, who have accused her of being an agent for the Muslim Brotherhood and Hamas, seeking to destroy the alliance between the US and Saudi Arabia.
Omar's stances regarding human rights in Egypt have also led to her being accused of "supporting terrorists" by right-wing US media.