Colombian troops are also the target of false accusations, says President Uribe
Colombian authorities have arrested more than 20 soldiers, accusing them of killing civilians and passing the victims off as gunmen killed in combat.
An inquiry is currently under way into the cases of some 1,500 civilians believed murdered by troops since 2004.
The soldiers are accused of killing civilians and presenting them as rebels or paramilitaries to inflate army statistics in their security drive.
Last year, 27 soldiers and officers were fired when the scandal broke.
More cases have since come to light, with some said to involve killings as recently as last October.
Over the past week, the authorities have issued dozens of arrest warrants and detained more than 24 soldiers and officers, including three colonels, in connection with extra-judicial killings.
The attorney-general's office is investigating the deaths of 1,500 civilians believed murdered, unarmed and in cold blood, by members of the security forces.
In October, three generals and 11 colonels were among the 27 who lost their jobs, accused of either being directly involved in extra-judicial killings or being negligent and allowing their men to murder civilians.
The killings have become known as "false positives" where soldiers kill civilians and then either dress them up in uniforms or leave weapons by the bodies to suggest they were armed fighters.
President Alvaro Uribe, who has pursued a tough line against left-wing guerrillas, said on Wednesday that human rights abuses should be investigated and punished.
But he said police officers and soldiers should also not become victims of false accusations aimed at undermining the work of the armed forces.
"Just as there are human rights violations, which should become known and punished, and we hope become a thing of the past ...there are also plenty of false accusations," Mr Uribe said.
"Just as we have to demand total transparency from our soldiers and police, we also have to demand total impartiality from the justice system."
The UK government said last month it was halting military aid to Colombia, citing concerns that officers and soldiers had been involved in abuses.