Colombia's notorious Mobile Anti-Disturbance Squad (Esmad) has been deployed at the National University of Colombia, where faculty and students are resisting management-inspired reforms.
Human rights lawyers protested after Esmad attacked students taking part in a peaceful demonstration, injuring three.
The university wants to reorganise its structure into larger faculties and introduce other managerial changes, claiming that academic standards are deteriorating. This is challenged by faculty, who argue that exam results at the National University exceed those of elite private universities.
Esmad is also implicated in the fatal shooting of a student in September.
Johnny Silva, a chemistry student at the University of Valle, was allegedly shot by riot police after they stormed the university to quell protests about cuts to water supplies and planned trade agreements with the US.
Witnesses say Esmad used teargas, rubber bullets and live ammunition on protesters, detaining about 20 students.
"Unprovoked brutal police attacks against students who voice opinions against the Government are nothing new," said Gabriel Becerra of the Colombian Association of University Students Union (Aceu).
According to Aceu, attacks against student activists and the use of excessive police force during peaceful protests have increased since Alvaro Uribe Velez became President in 2002. Aceu said that between 2002 and 2004, 47 students were killed, 52 received formal death threats and 12 were disappeared. It said student leaders were detained and their homes raided by state agents.