A court in Bangladesh has sentenced the Nobel laureate Muhammad Yunus to six months in jail for violating the country's labour laws.
Prof Yunus has been a vocal critic of Prime Minister Sheikh Hasina.
His supporters say the case is politically motivated.
The acclaimed economist and three colleagues from Grameen Telecom - one of the firms he founded - were found guilty of failing to create a welfare fund for their workers.
All four deny any wrongdoing and have been granted bail pending appeals.
"As my lawyers have convincingly argued in court, this verdict against me is contrary to all legal precedent and logic," Prof Yunus said in a statement released after the verdict.
"I call for the Bangladeshi people to speak in one voice against injustice and in favour of democracy and human rights for each and every one of our citizens."
The 83-year-old Yunus, known internationally as the "banker to the poor", is credited with establishing a pioneering system of micro-finance loans helping to lift millions out of poverty.
Prof Yunus and his Grameen Bank were jointly awarded the Nobel Peace Prize for their pioneering work in 2006.
Discussing the verdict, one of his lawyers, Abdullah Al Mamun, told the BBC: "It was an unprecedent judgement. No due legal process was followed in the case and it was rushed through."
Mr Mamun added: "The whole idea is to damage his international reputation. We are appealing against this verdict."
Prof Yunus's lawyers say he is facing more than 100 other charges over labour law violations and alleged graft.
Ms Hasina once described Prof Yunus as a "bloodsucker" of the poor and accused Grameen Bank of charging exorbitant interest rates.
Irene Khan - the former head of rights organisation Amnesty International who works as a UN special rapporteur - was present at Monday's verdict. She told the AFP news agency the conviction was "a travesty of justice".
In August, more than 170 global figures called on Ms Hasina to stop the "persecution" of Prof Yunus.
The letter, whose signatories included former US Secretary of State Hillary Clinton, Virgin Group founder Richard Branson and U2 lead singer Bono, asked that the "continuous judicial harassment" of Prof Yunus be stopped.
Ms Hasina said she welcomed international experts to assess the ongoing legal proceedings against Prof Yunus.
It is not clear what led to the friction between Ms Hasina and Prof Yunus, but supporters of the economist said the government was attempting to discredit him because he once considered setting up a political party to rival the governing Awami League.