Brazil's President Luiz Inácio Lula da Silva has sacked the deputy director of the national intelligence agency and four department heads.
Investigations continue into claims the agency, Abin, illegally spied on ex-president Jair Bolsonaro's enemies.
The deputy, Alessandro Moretti, is accused of passing information to former Abin boss Alexandre Ramagem, a politician for Mr Bolsonaro's party.
Mr Bolsonaro says he and his family are being persecuted.
Lula has rejected that claim, saying his government does not give orders to the federal police.
The scandal first broke on Thursday when Brazil's Supreme Court unsealed documents in which Abin was accused of carrying out surveillance on key political and judicial figures critical of the former president.
Among the alleged targets of the illegal eavesdropping were three Supreme Court justices and a speaker of Brazil's lower house of Congress.
Supreme Court Justice Alexandre de Moraes said police had identified Mr Bolsonaro's son Carlos as part of the "political nucleus" suspected of ordering the illegal spying.
The judge authorised raids on Monday on the home and offices of Carlos, who is a Rio de Janeiro city councillor.
Carlos Bolsonaro's lawyer did not immediately respond to a request for comment from the Associated Press news agency.
Last week, police searched the office and home of Mr Ramagem, who has denied wrongdoing, Reuters news agency reports.
Police suspect Abin used Israeli software known as FirstMile to monitor mobile phones illegally.
Veteran leftist Lula narrowly beat Mr Bolsonaro, a far-right politician, in a tense presidential run-off election on 30 October 2022.
This latest probe adds to the legal problems of Mr Bolsonaro, who has been banned from running for office for eight years after casting unfounded doubts on Brazil's electronic voting system.