Niger says it made a mistake in arresting 59 people for being followers of al-Qaida following a deadly clash last month.

The governor of Agadez, Garba Maikido, issued an apology on national television Friday, saying the 59 were actually just migrant workers hoping to smuggle themselves into a neighboring country.

Niger arrested the 59 migrants last month in the mountainous Air region in the northern part of the country. At the time, officials said a clash with al Qaida militants had resulted in the deaths of three militants and one soldier.

Niger officials now say that the arrests were the result of an incident with the driver of the truck carrying the migrants, who was killed in a scuffle with the soldiers.

State-run media reported that Maikido and officials went to the home of the driver to apologize to his family.

The 59 migrants have been released. Niger says the incident is under investigation.

The militant group – al-Qaida in the Islamic Maghreb – operates across the Sahel, a strip of land that separates the Sahara desert from the rest of Africa. The group has carried out kidnappings and killings in Mauritania, Algeria, Mali and Niger.