President Magufuli received more than 12 million votes while top opposition figure had only two million.
The Tanzanian police have released three opposition leaders who were arrested on Monday after they called for demonstrations to demand fresh elections and an independent electoral commission.
Chadema, the leading opposition party, said on Tuesday its chairman Freeman Mbowe, and fellow leaders – former legislator Godbless Lema and former mayor of Ubungo municipality, Boniface Jacob – were released.
“Mbowe, Lema and Jacob have been released … on bond by the police,” Chadema said on its Twitter account.
The opposition demanded a rerun of the election, citing widespread suspected fraud, and has called for protests against the outcome, which saw incumbent President John Magufuli win with 84 percent of the vote on October 28.
Separately, police also released Zitto Kabwe, head of another fast-growing party, ACT-Wazalendo, a party official said.
Police had arrested Kabwe earlier on Tuesday while he was visiting the now-released Chadema leaders at the station where they were being held.
“We are seeking details on whether he has been released on bail or not and when he is supposed to report back [to the police station],” said Janeth Rite, ACT-Wazalendo’s deputy secretary of ideology and publicity.
Kabwe was among leaders sought by police after the former legislator called for peaceful protests on Saturday.
Police said the protests were illegal and aimed at fomenting violence.