Tanzania’s president on Wednesday openly expressed doubt about covid-19 vaccines and accused people who were vaccinated outside the East African nation of bringing new infections into the country.

“If the white man was able to come up with vaccinations, then vaccinations for AIDS would have been brought, tuberculosis would be a thing of the past, vaccines for malaria and cancer would have been found,” President John Magufuli said during an event in his hometown.

He also warned against Tanzanians being used as “guinea pigs” for the vaccines.

Magufuli, who offered no evidence to support his doubts, has been widely criticized for declaring the coronavirus defeated in Tanzania. The country hasn’t updated its number of confirmed infections since the middle of last year: 509

But now other authorities in the country, including the Catholic church, appear to be pushing back as parts of the African continent see a strong second surge in virus infections.

Magufuli also suggested that donated vaccines are part of a conspiracy to steal Africa’s wealth: “Don’t think you are loved so much. Tanzania is rich. Africa is rich. Everyone wants a piece of it.”

The president in the past has told Tanzanians not to implement social distancing while encouraging them to use untested herbal remedies to treat the disease. He also questioned the credibility of donated virus tests.

Some people who opposed the government’s stance that Tanzania was coronavirus-free were arrested and charged.

Magufuli won a second five-year term in office in an October election which opposition leaders blasted as a “butchering of democracy.”