Magufuli has been criticized for being arrogant and autocratic when dealing with opponents, either perceived or real.
“They should be careful. I can decide in two or three days to change the currency,” he said.
During five years as minister of works, Magufuli earned his nickname, the Bulldozer, for his habit of pushing aside any obstacle in order to get what he wants.
As president, he often takes a similar approach. In April, he fired more than 9,000 government workers over fake education certificates.
His no-nonsense ways can get results. For instance, the government is building a railway, roads, and pipelines to connect the country to neighboring Uganda.
But his methods leave activists and the opposition concerned.
Opposition lawmaker Zitto Kabwe said Magufuli’s approach is shortsighted.
“We have a president who hates multiparty democracy. He might be developmental, he would like to see the country going forward, but he hates democracy, and without democracy, development is not sustainable, because without democracy the institutions of accountability, the inclusive institutions that will enable the country to move forward will not develop,” said Kabwe.
Human rights groups have accused the government of using repressive legislation to muzzle the media and civil society.
The laws have been used against Maxence Melo, the co-founder of Jamii Forums, a whistle-blowing website.
The website was dedicated to exposing corruption in Tanzania. But Melo was accused of obstructing an investigation and failing to register the website with the state.
Melo said the authorities need to stop seeing critics as enemies.
“You need the media to fight corruption. Whatever fight he [Magufuli] is trying to fight, the anti-corruption kind of drive, it is the same thing as we the media revealed. We are the ones who made sure this thing is getting to the parliament,” said Melo.
Political analyst Azaveri Luwaitama said the ruling CCM party is afraid of losing power, after 56 years of rule.
“The reality on the ground between 2010 and 2015 was that this party had lost its legitimate appeal to being inclusive. So they organized an election and made sure that they won, but there is uncertainty. So they are trying to crush the opposition so that they can sort out things within themselves,” said Luwaitama.
In the 2015 election, President Magufuli received 58 percent of the vote, a big drop from previous elections in which 80 percent of Tanzanians voted for the CCM party.