The Philippine government has issued an order barring Joseph Estrada from leaving the country.
His wife and one of his sons are also included in the order.
The former president is facing an inquiry into allegations that he stashed away millions of dollars in bribes.
Tax collectors say they are ready to freeze bank accounts linked to Mr Estrada.
More than 100 protesters gathered outside two Manila banks, vowing to prevent him from gaining access to accounts he allegedly has there.
Senators have considered renewing impeachment proceedings against the former action film star, who was forced out of office on Saturday after three days of swelling protests.
Senate President Aquilino Pimentel says he wants to "wind up the proceedings" and is to meet Chief Justice Hilario Davide, the presiding officer at the trial.
Mr Estrada is under investigation on suspicion of plunder, misuse of funds, graft, perjury, bribery and possession of unexplained wealth.
Nelson Aspe, an officer of the Bureau of Internal Revenue, says his agency expects orders to freeze bank accounts linked to Estrada.
The Justice Department's "hold departure" order bars 24 people, including former first lady Loi Ejercito, Mr Estrada's son Jinggoy and several other suspects, from leaving.