ALGIERS (Reuters) - Algeria has repatriated 27,000 sub-Saharan African migrants since 2015 and will continue to send them back to their home countries despite criticism from rights groups, interior minister Nouredine Bedoui said on Thursday.

Algeria is both a destination and a country of transit for African migrants seeking economic opportunities and fleeing poverty, repression and instability.

Those who stay in Algeria mostly come from Mali, Niger, Burkina Faso or Chad and many find work on construction sites.

Some travel through Algeria to neighboring Morocco or to Libya, which remains the main departure point for migrants trying to reach Europe by sea.

“We have already repatriated 27,000 illegal African migrants to their countries since 2015,” Bedoui told parliament in Algiers, giving a rare official figure for the number of people sent home.

“The operation of repatriation is still ongoing.”

Bedoui said Algerian authorities had disbanded several groups involved in migrant smuggling, but warned that such networks were still active.

Activist groups including Human Rights Watch (HRW) and Amnesty International have sharply criticized the repatriation of migrants by Algeria.

Last month HRW said Algeria was rounding up and deporting migrants “in a degrading way” without giving them a chance to have their cases individually reviewed.