The 73 migrants taken aboard the Open Arms vessel early Thursday morning include four women, 24 unaccompanied minors and two children aged 3 and 4, the NGO said on Twitter.

Some of the migrants suffered from shock and "second to third-degree burns, gunshot wounds, severe hypothermia and dehydration,“ Proactiva Open Arms added.

The migrants had embarked in the Libyan port town Zawiya. They contacted the distress hotline Alarmphone when they experienced distress at sea. Alarmphone said that it notified maritime authorities and the Open Arms vessel which then located the distressed boat. The crew found the migrants crammed in a dinghy whose engine had broken down, said spokesperson Laura Lanuza.

Reuters reports that most of the migrants are from Central and Western Africa. One young man from Niger was suffering from gunshot wounds which he said were sustained in a Libyan detention center in early November, Reuters cites.

Nearly 200 migrants in two vessels

Meanwhile, over 120 people were taken aboard the Ocean Viking between Tuesday and Wednesday. The rescue ship is operated by SOS Mediterranee and Doctors Without Borders (MSF). After initially picking up 94 migrants on Tuesday, it encountered at least 30 migrants in a second rescue operation on Wednesday afternoon.

Among the rescued migrants on the Ocean Viking were four pregnant women and 42 minors, including six children under 12, SOS Mediterranee said. 

At 1 pm (1200 GMT) on Thursday, the Ocean Viking ship was positioned north of Tripoli, while the Open Arms was located between Italy's Lampedusa island and Malta, according to information on the Marine Traffic website.   

The Open Arms vessel is seeking disembarkation at a European port. "We would like a response from a functional government, which leaves Italy or Malta. The closest safe port to us is in Italy," said Open Arms mission chief Ricardo Gati. "We're waiting to see what the response is and how long we have to wait."