CNN  — 

President John Magufuli, the Covid-denying leader of Tanzania, was said to have died from heart failure, which he apparently battled for more than a decade, according to the country’s new president.

Samia Suluhu Hassan said Magufuli had been receiving treatment in a Tanzanian hospital when he died on Wednesday evening.

However, opposition leaders insist Magufuli died of Covid-19 at least one week earlier.

Tundu Lissu, of the Chadema opposition party, said in an interview with a Kenyan broadcaster Thursday that Magufuli had died from Covid in early March.

“Magufuli died of corona,” Lissu said, citing “credible government sources.”

“I received news of President Magufuli’s passing without any surprise,” he added.

“I had expected this all along, from the first day I tweeted on March 7… when I asked the question ‘Where is President Magufuli and what is his state of health?’ I had information from very credible sources in the government that the president was gravely ill with Covid-19 and his situation was actually very bad,” Lissu said from his base in Belgium. CNN has contacted Lissu for further comment.

CNN has been unable to independently verify his claims. Tanzanian authorities also did not respond to calls for comment on Lissu’s claims.

Magufuli was last seen in public on February 27, fueling intense speculation about his health. Officials, however, insisted he was healthy.

“Tanzanians should be at peace. Your president is around, thanks for voting strongly for him recently. He is healthy, working hard, planning for the country,” Prime Minister Kassim Majaliwa was quoted as saying in local media March 12.

The secrecy and mystery shrouding his death is telling about Magufuli’s enduring legacy, says Maria Sarungi Tsehai, activist and founder of the #ChangeTanzania movement, a civil society group promoting free speech.

Tsehai said that the circumstances of his death and the “secrecy and intimidation” that citizens face for speculating or discussing it is “very telling about the kind of presidency he ran.”

“Even now in his death, people are still terrified and talking in hushed tones,” Tsehai said.

Magufuli was Tanzania’s fifth president and part of the Chama Cha Mapinduzi (CCM) party that has ruled the country since independence in 1961.

Now that he is gone, Tanzania is left in flux. Many believe the country is fighting a virulent second wave of Covid. However, the reports are largely anecdotal as Tanzania stopped reporting Covid data to global health authorities, such as the World Health Organization.

The last reported figures of 509 cases and 21 deaths were in April last year.

Magufuli frustrated global health leaders after he suspended nationwide tracking of Covid cases – blaming the country’s infection toll on defective test kits.

Last May, he claimed that non-human samples which were randomly collected from a pawpaw, a goat, and sheep – using imported Covid-19 test kits – returned positive test results for the virus when sent to the country’s laboratory, whose handlers were reportedly unaware of the source of the samples.

Magufuli’s death has raised many questions about how the country moves forward in a pandemic with a massive information vacuum.

Magufuli made no bids for Covid vaccines as he queried its safety and instead promoted the use of prayers, herbal treatments and steam inhalation to combat the disease.

Tsehai says the lack of information makes it difficult for healthcare workers and citizens to know what the real situation is. Her organization ran an informal survey to get a “snapshot” of the Covid situation in the country last year.

“We are seeing more obituaries, death announcements, and that more people are leaving us. There are elderly people and those in their 50s. Parents are also telling us that children are being admitted to hospital with breathing problems,” she said.

However, changes are far from imminent, added Tsehai. “Nothing will happen immediately. We have to wait and see what Samia (Hassan) can do.”