Boris Nemtsov Funeral
People stood in line to attend a memorial service before the funeral of Russian leading opposition figure Boris Nemtsov in Moscow, March 3, 2015. Reuters

Anna Duritskaya, the Ukrainian model girlfriend of slain Russian opposition leader Boris Nemtsov, has received death threats in the days since she was identified as the sole witness to his murder, prosecutors in Ukraine said Friday. The 23-year-old has purportedly gone into hiding amid concerns about her safety.

“Duritskaya… filed a statement about the threat to her life from unidentified people during her time in her parents’ home,” Ukrainian prosecutor general Viktor Shokin said in a statement, according to Agence France-Presse. Authorities will ensure “all necessary measures are taken to protect the life and health” of Duritskaya in the face of these unspecified death threats, Shokin added.

Duritskaya spent time at her parents’ home in Kiev, Ukraine, after her release Monday by Russian authorities in Moscow. Police interrogated Duritskaya for three days after Nemtsov, her boyfriend of four years, was shot four times and killed by an unknown assailant Feb. 27 on Moscow’s Great Moskvoretsky Bridge near the Kremlin. He and Duritskaya had just left a nearby restaurant.

Duritskaya was so concerned about her personal safety that she skipped Nemtsov’s funeral Tuesday, according to the Los Angeles Times. She deleted all of her social media accounts and fled the public eye with her mother.

Russian investigators say they have yet to determine who is responsible for Nemtsov’s murder. Authorities told state-run media they are attempting to determine if a foreign element played a role in the opposition leader’s death. Duritskaya has remained adamant that she has no information on who may have acted against her boyfriend.

“I do not know who did it. I do not want to answer any more questions about what happened on the bridge. I do not want to talk about it,” Duritskaya told independent news outlet Dozhd in a Skype interview earlier this week, before Russian authorities consented to her departure. “I gave all the testimony that I could, so I do not know why I am still on Russian territory.”

Duritskaya works as an actress and model. She attended Kiev University.