“Most of the money is missing. If you ask questions, you will be told that they are in an account in China," President Samia Suluhu said on Tuesday at an event launching the investigative commission.

In 2019, Ms Samia’s predecessor John Magufuli amended the criminal laws to introduce, among other changes, a plea-bargaining arrangement, where detained suspects and convicts bought their freedom or got lesser sentences.

According to the government's audit office, the office of the Director of Public Prosecutions (DPP) had collected at least $21m (£17m) by April 2021.

Ms Samia did not however give the exact figures of how much was missing and the owners of the said offshore account.

During Magufuli's administration, millions of dollars were squeezed from businessmen, who were accused of serious economic crimes, in plea-bargain deals.

A high-profile economic crimes case settled under the arrangement involved the owner of Independent Power Tanzania Limited, Harbinder Seth Singh, who was freed after paying $11m, four years after his arrest in 2017.

Among many others, investigative journalist Eric Kabendera in February 2020 paid over $70,000 to be free, according to the courts.

Mr Kabendera was arrested on charges related to money laundering, tax evasion and leading a gang of organised crime. His arrest was criticised by human rights groups who said Magufuli was punishing critics and the media.