Colombia's new President Alvaro Uribe has declared a state of emergency to fight what the government described as a "regime of terror" following a surge of war violence.
The new measures were decreed late on last night under the power of a state of emergency Uribe enacted shortly after taking office in August.
Human rights groups said the measures needlessly restricted civil rights and targeted civilians instead of combatants in a 38-year-old war claiming thousands of lives a year.
But Uribe, 50, who was elected promising to get tough on leftist rebels and enjoys an approval rating of about 70 percent, said authorities needed the new powers to fight leftist rebels and far-right paramilitaries, who are funded by money from the cocaine trade.
"If you read them carefully, you will see that they entirely respect human rights. I welcome the controversy. The measures aren't meant to silence controversy, but to face up to terrorism," Uribe told reporters.
The Colombian authorities often use the word "terrorism" to equate their struggle with the global offensive being waged by their ally and major aid donor the United States - which is an enthusiastic supporter of the Uribe administration.
An official at the Colombian Jurists' Commission, a non-governmental organization, said it was outrageous that security forces would now be able to hold suspects for 24 hours without presenting them to a state prosecutor.
"They allow security agents to enter your house or office without a warrant at any time of day because they think you're suspicious," said the commission's head, Gustavo Gallon.
The emergency powers, which will allow military commanders to declare curfews and control movements in areas which will be called "Zones of Rehabilitation and Consolidation", have even worried some members of Uribe's own Liberal Party.
"This will end up allowing abuses and raising questions abroad and in Colombia about the legitimacy of the government's fight against criminals," said Sen. Rodrigo Rivera.
The U.S. government earlier this week approved more military aid for Colombia, after deciding it was doing enough to protect human rights. Senior military officers have been investigated for links to far-right paramilitaries who have massacred civilians in recent years, but Uribe says he will crack down on far right and far left outlaws alike.
Colombia's new emergency measures are in many aspects less draconian than the powers enacted by the U.S. government to deal with foreign suspects, said Robin Kirk, of Washington-based Human Rights Watch.
Human rights groups are also worried about Uribe's plans to set up a network of one million civilian informants, which they fear could allow anonymous snoops to make malicious accusations against neighbors to the security forces.
The government sees informants as key to re-establishing state control over the roughly 50 percent of Colombia which, in decades of low-intensity fighting, has fallen under the sway of leftist rebels or paramilitary vigilantes.
The informants plan is also cheap. Uribe plans to boost defense spending by one third but Colombia's military is still undermanned and under-equipped, despite receiving massive aid from the United States to fight cocaine.
Uribe says that Colombia's conflict will only finally be solved by peace talks, and promises to boost social, as well as military, spending in order to fight poverty.