The Mauritanian coastguard said Thursday that it had rescued more than 160 migrants, including 17 children, from a boat in trouble off its coast, its second major emergency operation in a week.
The migrants were "exhausted by the journey and the insecurity of the vessel" when they were rescued on Tuesday, a coastguard statement said.
Last Friday, a coastguard vessel took more than 300 migrants from a boat drifting off the west African country's Atlantic coast.
Hundreds of people, mostly from Senegal, The Gambia, Guinea and Mali, have been rescued in Mauritanian waters in recent months while attempting to reach Europe. Hundreds have also died or gone missing after their boats sank.
"The boat had set out to sea from Banjul, the capital of The Gambia, and had sailed for about eight days on the open sea before being spotted by coastguard units, which intervened to rescue everyone on board," the coastguard said.
"All the people on the boat are safe and sound, but particularly exhausted by the journey and the insecurity of the vessel, which already had a problem with its engine," it added.
The 161 people were taken to a reception centre in the capital, Nouakchott.
Thousands of mostly young people have for years attempted the perilous Atlantic route on overloaded and often dilapidated boats to reach Europe via Spain's Canary Islands.
Many are fleeing poverty and resort to clandestine and rickety boats as European countries have drastically restricted the issuing of visas and tightened control over their borders.