Bechir Akremi and Tayeb Rached, who were among the dozens of judges and members of the judiciary sacked in 2022, were detained by police, Anouar Awled Ali, a lawyer close to the cases, told Reuters.
The local Mosaique FM radio network said Akremi's arrest was linked to the investigation into the assassination a decade ago of Chokri Belaid, a political activist. It added that Rached's arrest was due to suspicion of financial corruption.
The arrest of the two former judges came after police detained on Saturday a number of people on suspicion of conspiracy against state security.
Among those arrested was former Finance Minister Khayam Turki, Abd El Hamid Jlassi, a former senior official in the Ennahda Islamist party, and Kamel Ltaif, a businessman with close ties to successive coalition governments.
Ennahda, the biggest opposition party, said the arrests were aimed at intimidating opponents of Tunisia's president.
A spokesperson for the Interior Ministry did not immediately respond to a request for comment on the arrests.
Saied's political opponents, whom he has labelled traitors, have accused him of a coup aimed at dismantling the democracy built after a 2011 revolution.
The president has denied those accusations, saying his moves were lawful and necessary to save Tunisia from chaos. He has promised to uphold rights and freedoms won in the revolution.
Over recent months, authorities have arrested or opened investigations into several of Saied's political opponents.
Rights groups have voiced increasing concern over political freedoms in Tunisia since Saied's seizure of most powers in 2021 and his moves to assume ultimate authority over the judiciary.
A spokesperson for the Interior Ministry did not immediately respond to a request for comment on the arrests.
