The federal police force in Mexico has sacked almost 10% of its officers in an effort to combat corruption.
The 3,200 fired officers had either failed to do their job properly or had been linked to corruption or organised crime, said Commissioner Facundo Rosas.
Mr Rosas said more than 1,000 others faced disciplinary proceedings and might also be sacked.
He said none of the officers would be allowed to work in police forces at local, state or federal levels.
More than 4,500 officers have been sacked since May, said Mr Rosas - many had been charged with crimes.
At a news conference, Mr Rosas, said some of officers had been accused by subordinates of having links to drug cartels in Ciudad Juarez, the country's most violent city.
The commissioner said this was only the first stage of a purge of Mexico's forces and that more than 1,000 others faced disciplinary proceedings and may also be sacked.
Soon after taking office, President Felipe Calderon launched an all-out war against the drug cartels.
In many parts of the country he has deployed the army against the traffickers despite the opposition of many of his critics.
But Mr Rosas said the federal police force was also taking part in the drugs war.
He said the ongoing purge was part of a strategy to rid the police of corruption and make its 34,500 officers more reliable, as they were an integral part of the country's security forces.
The war against the drug cartels has left some 25,000 people dead since Mr Calderon came to power in December 2006. BBC News
