Tunisia's interior ministry has announced it is dissolving the country's secret police service.
The agency had been widely accused of committing human rights abuses during the rule of President Zine al-Abidine Ben Ali, who was ousted on 14 January.
Interim Prime Minister Caid Essebsi has also announced a new government, which includes no members of the old regime.
The interim government is running Tunisia until elections scheduled to take place on 24 July.
The interior ministry announced online that it was disbanding the State Security Department, under which the secret police operated, and would respect "civic freedoms and rights".
The move was a "definitive break with any form of organisation resembling the political police at the level of structure, mission or practice," it said.
"These practical measures are in harmony with the values of the revolution, in the wish to respect the law, in word and deed, and in consecrating the climate of confidence and transparency in the relationship between the security services and the citizen," the ministry said in a statement.
The secret police had played a key role in suppressing the opposition in the country.
Human Rights Watch said members of the agency "hounded dissidents, tortured Islamists, and shook down their compatriots".
The BBC's regional analyst Magdi Abdelhadi says dismantling the agency had been a key demand of the opposition, so the move will be seen as the ultimate victory over the Ben Ali regime.
The announcement came shortly after Mr Essebsi named the new interim government which contains no members of the former regime.
The new line-up retains most of the key ministers from the previous interim administration, including those for defence, interior, justice and foreign affairs.
But a number of new appointments have been made following a spate of resignations last week which included Prime Minister Mohammed Ghannouchi.
He was seen by the protesters as being too close to the old regime.
Members of the government will not be allowed to stand as candidates in future elections.
Tunisia has struggled to restore stability since mass protests ousted Mr Ben Ali.
The victorious protesters have been demanding that the new leaders move faster to bring about political and social change.
However, other Tunisians have been urging the protesters to return to work and bring an end to the rallies.
With the two announcements on Monday, our correspondent says the Tunisian revolution appears to have met two of its main goals.