Tunisian opposition leader Rached Ghannouchi has been remanded in custody following his arrest earlier this week, his Ennahdha party said on Thursday, denouncing his "unjust imprisonment".
Ghannouchi, a former speaker of parliament, was arrested on Monday after remarks warning that eradicating different viewpoints such as the left or political Islam, from which his party originated, might lead to a "civil war".
The main opposition alliance, the National Salvation Front (FSN), of which Ennahdha is a member, said he had been held on suspicion of "plotting against state security".
Ghannouchi's lawyer Mokhtar Jemai, said the court ordered his client's detention after more than nine hours of questioning. Ghannouchi is 81 years old.
Ennahdha rejected any suggestion that Ghannouchi was calling for a civil war, saying it "strongly condemns an unjust ruling which aims to cover up the total failure of the authorities to solve economic and social problems".
Tunisia is heavily indebted and facing high inflation and unemployment, leading some of its citizens to try fleeing to Europe.
Since early February, authorities in the north African country have arrested more than 20 political opponents and personalities.
Ennahdha dominated dissolved parliament
The Islamist-inspired opposition Ennahdha party held the most seats in Tunisia's parliament before President Kais Saied dissolved the chamber in July 2021 in a power grab allowing him to rule by decree.
Saied claims those detained were "terrorists" involved in a "conspiracy against state security".
Opponents have dubbed his actions a "coup" and have condemned a return to autocratic rule in the only democracy to emerge from the Arab Spring uprisings in the region more than a decade ago.
Tunisia has been negotiating for several months with the International Monetary Fund for a loan of nearly $2 billion, but discussions appear to have stalled.
On Tuesday the 27-nation European Union expressed "concern" following the arrest of Ghannouchi, recalling the importance of the "fundamental principle of political pluralism".
The United States on Wednesday condemned the arrests of political opponents and said respect for freedom of expression and human rights are essential "to the US-Tunisia relationship".
Tunis hit back with a strongly worded statement on Wednesday, calling them an "unacceptable interference".
