The president of a non-profit Christian NGO is under the protection of U.S. law enforcement after reportedly receiving death threats.

China Aid president Bob Fu's regular criticisms of the Chinese Communist Party (CCP) are being considered a possible reason for the threats, Mission News Network reports.

The non-governmental Christian non-profit focuses on international human rights and exposing violations of these rights. China Aid has regularly criticized the CCP for its own human rights violations. They also seek to promote religious freedom in China.

The organization believes a former Chinese businessman who was accused by Chinese authorities of bribery, fraud, and money laundering may be behind the threats against Fu.

Wengui fled to the United States after he was accused of these crimes and now runs social media platforms that have gained popularity, on which he encourages his followers to take violent measures against those who have spoken out against the CCP.

Fu is one such frequent critic of the CCP, MMN reports.

In October, protestors gathered outside Fu's home in Texas and accused him of being a spy for the CCP.

The purpose of waging such a war against Fu could serve to discredit the China Aid leader and impair his work.

Greg Musselman of Voice of the Martyrs (VOM) Canada says it remains unclear who is behind the threats but that Fu has been under threat and "that's being taken very seriously."

Musselman also says protestors have been "handing out flyers saying that he's a fake pastor, he's an evil cheater. There were even protest signs declaring that he is a Chinese spy."

Officials believe the CCP itself may be targeting Fu.

Musselman says Fu is well respected and will not stop the work he is doing based on their threats.

"He was arrested for starting an underground church in China. He was involved in Tiananmen Square," Musselman says.

"Bob has been in the White House, he’s had many members of the Senate, Congress, even mayors. He is well respected. And what he says is taken with a lot of seriousness."