Among the rescued migrants who have been taken to detention are 16 women and 19 children, according to an IOM tweet.
"We reiterate that the arbitrary detention system in Libya must be dismantled," IOM noted.
More than 5,400 illegal immigrants have been rescued and returned to Libya so far this year, while the number is more than 9,200 in 2019, according to IOM.
Libya has been plagued by insecurity and chaos ever since the fall of the late leader Muammar Gaddafi's regime in 2011, making it a preferred point of departure for thousands of illegal immigrants who want to cross the Mediterranean Sea toward Europe.
Before the Libyan authorities closed all the country's borders as a precautionary measure against COVID-19, IOM had been running the Voluntary Humanitarian Return program that arranges the return of illegal immigrants stranded in Libya to their countries of origin.