Rubina Aminian was a "full of life" 23-year-old Iranian fashion student with big goals for the future. She was shot and killed last week amid the protests, her aunt told CBS News, as she described how Aminian's mother forced her way into a morgue and carried her daughter's body out.

"I can confidently say that it was the most difficult day of my life," Aminian's aunt, Hilala Noori, told CBS News, of the day she learned Aminian had been shot. "When they confirmed she had been killed, my whole body was burning. I don't know how to describe that moment to you. I've been unable to sleep for more than two hours since Saturday. I feel like a rock is in my throat. I cannot swallow anything."

On the evening of Jan. 8, Aminian left her university and joined the large crowds marching in the streets in the capital city. There, her family says she was shot at close range in the back of the head.

When Aminian's family heard the news of her death, they immediately left Kermanshah, where they live, and drove to Tehran to find her body, Noori said. 

They found out the location of the morgue where they believed her remains were located and went there to try to find and bring her home.

When they arrived, Noori said her sister, Aminian's mother, described seeing hundreds of bodies all "lying on top of each other." She said: "The children of people, all of them had been shot in their heads, their necks, directly in their heads. They were all lying on each other, and my sister was forced to see those beautiful faces in order to find our dear Rubina."

Noori told CBS News that Aminian's mother searched the bodies outside the facility, but couldn't find Aminian. She was initially not allowed inside the facility, but managed to force her way in.

"She [was] forced to carry her daughter's body and steal it, because they didn't give her permission to take out the body," Noori told CBS News. "She was forced to carry the body of her 40-kilo daughter and take her outside. She stole the body from them and held it for many hours until they arrived at Kermanshah," Noori told CBS News.

Noori said she holds Iran's Supreme Leader Khamenei, the Islamic Revolutionary Guard Corps and the Islamic Republic of Iran "directly responsible" for the death of her niece. "They are the only ones responsible for it," she said.

"What the Islamic Republic took from her, took from us, was a girl who was full of passion and love for life, and she shared that passion everywhere," Noori said. "She wanted to create her own future. She believed that you should create your own future with your own hands. She didn't wait for anyone to create her own future for her. Because of this, she took to the streets, to gain her freedom. Just like all the young people we've lost on the streets. She was hands-on; she never wanted anyone to do anything for her. She knew what she wanted to do, and she knew how to do it. And I'm really proud of her. I'm proud of her choice, even though it's very painful for me. I will have to live my life with this pain. I might never be the same. But I am proud of her, of her sacrifice, her path. And I hope that her blood has not been spilled in vain."

Noori said she hopes President Trump will take action against the current leaders of Iran.

"It's now time for action," she said. "It's not the time for him to think about what to do."

At least 12,000 — and possibly upwards of 20,000 — are now feared dead in Iran following more than two weeks of protests, sources told CBS News. President Trump, who for weeks has warned Iran of U.S. intervention amid a violent crackdown on protesters, said Wednesday he's heard on "good authority" that the "killing in Iran is stopping."