Nigeria’s justice minister has condemned as “unconstitutional” the early handover of power in Abia State between two men accused of corruption.
Theodore Orji won last month’s elections for state governor, even though he was in police custody.
He was freed on bail on Friday, ahead of Tuesday’s inauguration ceremony.
Outgoing governor Uzor Orji Kalu – who has also been suspected of corruption – stepped down early and has reportedly fled the country. Both deny wrongdoing.
‘Flagrant violation’
Mr Orji was sworn in at the Abia State liaison office in the commercial capital, Lagos, hours after he was freed on bail.
He then flew to Abia state with Mr Kalu, no relation, where they were greeted by thousands of cheering supporters.
Mr Kalu then reportedly returned to Lagos and flew out of the country.
Elected officials have immunity from prosecution.
Justice Minister Bayo Ojo said Mr Kalu was free to resign but could not hand over power to Mr Orji.
The government “condemns the flagrant violation of the constitution by former Governor Orji Uzor Kalu and his co-conspirators,” he told Nigeria’s ThisDay newspaper.
Nigeria’s anti-corruption agency, EFCC, has said it wants to investigate Mr Kalu on allegations of corruption.
Earlier this year, it also declared his mother a “wanted person”.
Both Mr Orji and Mr Kalu were members of the governing People’s Democratic Party but then switched to join the People’s Progressive Alliance.
Mr Kalu contested last month’s presidential election but was heavily defeated.
The EFCC has said it wants to investigate more than half of Nigeria’s governors on corruption charges.
It has warned that several could seek to leave the country before their mandates, and immunity from prosecution, expires on Tuesday.
Nigeria is regularly ranked as one of the world’s most corrupt countries by Transparency International.
Outgoing President Olusegun Obasanjo set up the EFCC to tackle corruption.