A/HRC/10/32 page 28 16. On 15 April, in Medellin, Antioquia, university students taking part in a peaceful demonstration that had been approved by the municipality were allegedly dispersed with violence and disproportionate force by the police Mobile Anti-Riot Squad. D. International humanitarian law 1. Guerrilla groups 17. OHCHR Colombia was informed of several mass killings allegedly carried out by guerrilla groups. The killing of three persons in Pensilvania, Caldas, on 14 February was attributed by the authorities to FARC-EP. In Santa Cruz, Nariño, FARC-EP allegedly murdered four teachers, three of them women, who had previously been kidnapped and held from 11 to 24 June, because FARC-EP believed them to be army informers. On 25 December alleged members of ELN murdered four members of the same family and one of their neighbours, a minor, and injured four other persons in Mata Oscura in Arauquita, Arauca. 18. OHCHR Colombia was also told of selective killings alleged to have been committed by guerrilla groups. In the department of Arauca the authorities attributed most of the 142 murders of civilians reported during the first nine months of the year to ELN and FARC-EP. 19. On 9 February, in Algeciras, Huila, FARC-EP allegedly murdered a journalist and local councillor as part of what appears to be a campaign against mayors and councillors in the region. On 30 April, in Ituango, Antioquia, the Office noted the killing, allegedly by FARC-EP, of a girl of 14 earlier accused of having a relationship with a member of the security forces. On 12 August, in Yarumal, Antioquia, FARC-EP is alleged to have murdered the municipal welfare director while he was on an official mission. On 17 October FARC-EP allegedly murdered the Chairperson of the Community Action Board of Tierra Alta, Cordoba, whom they accused of collaborating with the army. 20. ELN is alleged to have murdered the Chairperson of the Municipal Council of Saravena, Arauca, on 5 February. On 1 May, in Morales, Bolívar, ELN guerrillas allegedly murdered a person accused of collaborating with the army. They subsequently made threats against others in the same town, on the basis of the same accusations, resulting in the displacement of around 18 families. ELN allegedly killed the leader of the Arauquita Displaced Persons Association on 28 November in Arauquita, Arauca. 21. OHCHR Colombia also noted death threats from guerrilla groups. Several municipal attorneys also reported receiving death threats from guerrilla groups; on 23 January, for example, FARC-EP allegedly threatened the municipal attorney in Villarica, Tolima. 22. On 6 March FARC-EP set up a roadblock on the Samaná-Victoria (Caldas) road, where they are alleged to have killed the driver of a public transport bus and then burnt the bus. On 27 October, in the middle reaches of the Atrato River in Chocó, a municipal transport boat carrying 18 civilians was fired on, allegedly by FARC-EP, causing the death of 1 person and injuries to 4 others.