U.S. warns against traveling to Russia, 33-year-old dual Russian-American citizen detained while visiting family

"Do not travel:" That's the renewed warning from U.S. leaders as they reiterate a Level 4 travel advisory for American citizens in Russia.

The warning comes after a dual Russian-American citizen was detained in Russia, accused of treason for helping to raise funds for Ukraine.

Ksenia Karolina, 33, entered Russia on Jan. 2 to visit her family.

Her boyfriend Chris Van Heerden says they last spoke by phone on January 27.

Days later the U.S. was notified she was detained, accused of raising money to support Ukraine.

"Her fate is out of my hands and I feel powerless," says Heerden.

State department spokesman Matthew Miller says her dual citizenship may be a challenge .

"Russia has not recognized dual citizenship," he said. "Considers them to be Russian citizens first and foremost. And so oftentimes we have a difficult time getting consular assistance."

Stanislav Shwa-brin, Associate Professor of Russian at UNC Chapel Hill, says people should avoid traveling to the country.

"I would advise against traveling to Russia. We have not been sending students to Russia for some years now for all these same reasons," he said.

Shwa-brin says UNC is sending students to other countries where Russian is spoken, like Latvia, Lithuania and Estonia.

It's not just schools that are rethinking study abroad programs.

Karen Britt, with The Britt Travel Group tells WRAL, "Since Russia's invasion of Ukraine in February of 2022, travel to Russia for US travelers has been disrupted and has significantly changed the travel industry. "

Last year, the U.S. State Department issued a Level 4 Travel Advisory against travel to Russia, citing "the potential for harassment and the singling out of U.S. citizens for detention by Russian government security officials."

Officials are warning U.S. citizens who are there to exercise increased caution due to the risk of wrongful detentions.

Shwa-brin says the rule of law is non-existent under Russian President Vladimir Putin, who has been cracking down on dissent and support for Ukraine within Russia.

"This is a sworn enemy of individual freedoms," he said. "It's a sworn enemy of democracy that we're dealing with. His values, his interests are incompatible with what I can call our way of life."

Wall Street Journal reporter Evan Gershkovich has been held in Russia for nearly a year on espionage charges that he denies.