German charity Sea-Eye said it had rescued 78 migrants off the Libyan coast on Saturday and accused Libyan authorities of harassing rescuers and acting illegally.
The Alan Kurdi, named after a Syrian child whose drowning in the Mediterranean in 2015 brought global attention to the migrant crisis, received distress calls and rushed to aid migrants stranded on two boats.
"Our ship #ALANKURDI rescued 62 people from an inflatable boat in the morning. Water was already entering. Among them are 8 women and 7 children, the youngest just six months old," a Sea-Eye statement said.
"The #ALANKURDI found the second boat in distress and rescued another 16 people. Three people are severely dehydrated and were immediately taken to the on-board hospital for medical treatment," it added.
"The self-proclaimed Libyan coastguards treat the area of search and rescue operations as their territorial waters, harassing civilian rescuers and giving illegal instructions," Johanna Pohl, the head of operations on the Alan Kurdi, said, according to Sea-Eye.
The Alan Kurdi has been active since 2018 and has rescued hundreds of people so far.
The fall of Libyan dictator Moamer Kadhafi in 2011 turned the country into a key departure point for African and Middle Eastern migrants heading to Europe.
Since the start of the year, as many as 1,100 migrants have left Libya by sea, according to the International Organization for Migration, adding that a majority had been sent back to the country and detained.
At the behest of Italy, Libya's coastguard routinely blocks migrants from reaching Europe.
Rights groups charge that Libya picks up migrants in the Mediterranean and brings them back to overcrowded detention centres, where many have been victims of abuse and forced labour.
The Alan Kurdi has rescued hundreds of migrants since 2018