The African businessman looked fearful, glanced at nearby diners in a quiet restaurant and motioned silence.

The question had seemed innocuous: what did he think of John Magufuli, the Tanzanian president elected less than three years ago on high hopes and an anti-corruption platform?

But his reaction in the commercial capital of Dar es Salaam was mirrored across this East African nation of 55 million people.

Opposition figures live in fear and media freedom is no more. A decree in March required bloggers and social media operators to apply for a licence and pay US$900 per year, a staggering amount in Tanzania, before operating. A site “causing annoyance” can be shut.

Magufuli, the 58-year-old chemistry teacher, former Minister of Works and unexpected presidential victor, took office amid optimism that he would root out widespread corruption.

Hope has been replaced by fear that has muted criticism of or opposition to his rule.

The omens had been good when he was elected. He cancelled normally expensive and lavish Independence Day celebrations and urged people to clean streets, curbed foreign travel and first class tickets for officials and trimmed wasteful government spending.

At a micro level the numerous police roadblocks where bribes were the norm quickly went.

Police salaries rose and vehicle checks now come with on-the-spot fines documented and receipted.

Notoriously inefficient civil servants were fired on the spot as Magufuli toured the country making spot checks on government offices.

But the honeymoon soon turned sour.

Political opponents and hostile media figures have simply disappeared.

Any mention of the bodies of three opponents, two found on the city’s main Indian Ocean beach, overheard by police risks instant arrest, local residents say.

Political rallies are banned and residents say the police feel newly empowered by the president’s tone to take harsh action against anyone showing a whiff of opposition to his rule.

“Magafuli is becoming a dictator,” the businessman said later, away from hearing.

That is a turnabout from recent years when Tanzania did seem to be opening politically, albeit marred by endemic and widespread corruption.

Tanzania comprises the former Tanganyika which gained independence from Britain in 1961 and the Indian Ocean tropical spice island of Zanzibar which followed in 1963. They merged to form Tanzania in 1964.

Tanzania’s constitution was written in 1977 by Julius Nyerere, considered the nation's founding father, which gave sweeping powers to the president.

It’s a beautiful country and home to Kilimanjaro, Africa’s highest mountain, and national parks rich in wildlife like the Serengeti.

But the beauty belies the reality of growing authoritarian rule from the capital Dodoma by a president whom even his party, Chama Cha Mapinduzi or the Party of the Revolution' seem afraid to challenge.

The World Bank says Tanzania has had relatively high economic growth over the last decade, averaging 6-7 per cent per year, in a nation largely dependent on agriculture.

But while the poverty rate has declined the number of poor has not with 13 million people below the poverty line because of the high population growth.

Improving the economic outlook depends among other factors on a more significant role for the private sector, it says.

And yet foreign investors are deserting the country and rents in areas of Dar es Salaam where expatriates congregate are falling. “Business is dire,” said one taxi driver who once had a thriving business shuttling foreigners around town.

Extortionate tax demands have caused foreign companies to review their operations in Tanzania. Acacia Mining, a gold mining company, is looking to sell its operations after writing down its assets when Magufuli imposed an export ban on it. He accused the firm of understating its exports to avoid royalties and other taxes and demanded an extortionate US$190 billion in back tax.

On Zanzibar, a tropical paradise with spectacular beaches whose capital Stonetown is across a channel some 45 miles from Dar es Salaam, there are other challenges.

The 1.3 million people on the semi-autonomous string of islands are almost entirely Moslem (unlike the mainland which is mixed Christian and Moslem).

A growing number support secession from Tanzania, which they claim provides little support and inhibits the island’s potential as an Indian Ocean tourism gem.

The local government impose immigration and customs checks at the airport and marine terminal (a formality as these are already checked at mainland entry points).

A potential flashpoint in the whole of Tanzania is this Thursday (April 26), the Union Day anniversary of Tanganyika's and Zanzibar's merger.

A US-based Tanzanian social media activist has called for nation-wide anti-government demonstrations to protest about the loss of freedoms and human rights abuses.

Magufuli has warned: “Let them demonstrate and they will see who I am.” Police have declared any protests that day as “an act of treason” and one police chief suggested anyone demonstrating would “go home as cripples”.

The next election is 2020. Few hold out any hope of change and fear polling will be rigged in favour of Magufuli who is both head of state and chairman of the party with power to hire and fire civil servants, including judges.

An indication of the mood of the nation came from a wizened and very old man sitting in a village. “When the British were here, everything worked,” he said, surprisingly, of the now much-condemned era of British colonial rule.