Nigeria's former speaker of parliament who later became governor of Sokoto state has been arrested by the country's Economic and Financial Crimes Commission (EFCC) over corruption allegations

Aminu Tambuwal was detained on Monday at the commission’s headquarters in the capital, Abuja, over alleged fraudulent cash withdrawals of about 189 billion Naira ($123m).

It is unclear which of his former roles are related to the allegations. The 59-year-old Tambuwal was still being interrogated by Monday evening and has not publicly commented on the claims.

The alleged cash withdrawals are thought to have violated the Money Laundering (Prevention & Prohibition) Act, 2022, Nigerian news outlets report.

Tambuwal was the speaker of the House of Representatives between 2011 and 2015 and later became the governor of Sokoto state from 2015 to 2023. He is currently the senator for Sokoto South.

He is one of the leading opposition leaders promoting an opposition coalition, ADC coalition, which aims to unseat President Bola Tinubu in the 2027 general election.

EFCC’s spokesperson, Dele Oyewale, declined comment on Mr Tambuwal’s detention.