"I thank Allah that I have returned home safely. I thank all my fellow Tanzanians, and everyone around the world for their prayers," he said in a tweeted message.
"I thank the authorities of Tanzania, including the Police Force for working for my safe return."
His father Gullam Dewji confirmed his son's release in comments to the Tanzanian daily Mwanachi.
His uncle, Azim Dewji told Mwanachi the kidnappers had released him early Saturday in Dar es Salaam, Tanzania's economic capital.
"His abductors abandoned him and he was able to phone his father," he said in a video posted at the Mwanachi website, adding that his nephew was in good health.
The footage also showed a tired-looking Mohammed Dewji, in a tee-shirt and jogging trousers, thanking the police.
Abductors spoke 'African language'
Dar es Salaam police chief Lazaro Mambosasa told Mwanachi that he had already spoken with Dewji, who had told him that his abductors spoke an African language.
The family had offered a reward of half a million dollars (435,000 euros) for information that would help police find him.
Tanzanian police said Friday they had identified the driver of a vehicle used in the kidnapping and were making progress in their investigation.
Africa's youngest billionaire was kidnapped on October 11 by gunmen -- said to have been white -- as he entered the gym of a hotel in Dar es Salaam.
Mohammed Dewji, 43, heads the MeTL Group which operates in about 10 countries with interests in agriculture to insurance, transport, logistics and the food industry.
Police chief Lazaro Mambosasa told journalists that the assailants had "shot into the air" before bustling Dewji into their car.
Dewji was born in Tanzania and studied at Georgetown University in the United States. He also served as a member of parliament from 2005 to 2015.
In 2013, he became the first Tanzanian to grace the cover of Forbes magazine and was named Forbes Africa Person of the Year in 2015.
Dewji is also the main shareholder in Tanzania's Simba FC football club.
According to Forbes he is 17th on the list of Africa's billionaires, and worth $1.5 billion (1.29 billion euros).
Dewji is married with three children. In 2016 he signed a pledge to donate at least half of his fortune to philanthropic causes, according to Forbes.
Eyewitness? Submit your stories now via social or:
Email: eyewitness@pulse.ng
![The 10 warmest years have occurred since 2007 [Black Doctor]](data:image/svg+xml;charset=utf8,%3Csvg%20xmlns%3D'http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg'%20width%3D'300'%20height%3D'172'%20data-ring-placeholder%3D'1'%3E%3C%2Fsvg%3E "The 10 warmest years have occurred since 2007 [Black Doctor]")
