Colombian President Alvaro Uribe has defended his tough policies against insurgents in a speech before the European Parliament in Strasbourg.
Around 20 MEPs protested as Mr Uribe began his speech
Mr Uribe, who is on a five-day tour through Europe, said terrorism was itself a violation of human rights.
Some European legislators are critical of Mr Uribe's anti-terrorism laws which expand some of the military's powers.
About 20 MEPs left the chamber when he began to speak, holding scarves reading 'Peace and Justice in Colombia'.
One of the protesters, Green party group leader Monica Frassoni, said she considered Mr Uribe's visit "inappropriate".
"There are too many open questions about human rights violations," she said.
But in his address, Mr Uribe insisted his country's arrest and detention laws were no tougher than those in place in Europe and the United States.
"My people want iron determination to stamp out terrorism," he said.
Mr Uribe also ruled out a prisoner exchange with rebel group the Revolutionary Armed Forces of Colombia (FARC).
The group currently holds 50 high-profile hostages, which it wants to swap for rebels held in state prisons.
Mr Uribe said such a move would "open the doors to permanent blackmail of the state and society".
Earlier, Mr Uribe won support when he met European Commission President Romano Prodi in Brussels.
Mr Uribe won the support of the European Commission president
Mr Prodi backed Colombia's fight against left-wing guerrillas, despite widespread concern over human rights.
"[The Commission has] reaffirmed its commitment to support the government looking for a solution to the internal conflict" in Colombia, Mr Prodi said.
The Colombian president said he had received assurances that preferential trade ties would be extended beyond the end of the year.
Concern over legislation
Many European legislators are worried that Mr Uribe has failed to honour previous commitments on human rights.
He had pledged last year to improve his country's record in exchange for more EU aid.
Some members say they are particularly concerned about Mr Uribe's anti-terrorism laws which, among other things, expand the military's search and arrest powers.
Most of the president's critics say the measures could lead to an increase in the use of torture and forced disappearances.
Others are concerned about the controversial peace process with right-wing paramilitaries, especially because the Colombian Congress is currently debating a bill which could grant amnesty to these groups if they lay down their weapons.
Human rights organisations blame the paramilitaries for some of the worst atrocities in Colombia's 40-year civil war.