GENEVA - The U.N. human rights office said on Thursday that dozens of people were tortured by Mexican authorities and forces in connection with the government’s investigation into the 2014 disappearance of 43 students, and it called for a full inquiry.

“The findings of the report point to a pattern of committing, tolerating and covering up torture in the investigation of the Ayotzinapa case,” Zeid Ra’ad al-Hussein, U.N. High Commissioner for Human Rights, said in a report that documented torture based on interviews and medical records.

Mexico said on Monday it had arrested a suspected drug gang member regarded as a key figure in the kidnapping and massacre of the 43 student teachers. Activists say the case is emblematic of widespread violence in the country.

Mexico’s mission in Geneva said the ambassador was not immediately available to comment on the report.