A boat carrying about 500 migrants, including a newborn baby and pregnant women, has disappeared in the central Mediterranean, two charities said on Friday.
Alarm Phone, a group that picks up calls from migrant vessels in distress, said it lost contact with the boat on Wednesday morning.
At the time, the boat was adrift, with no working engine, in high seas about 320 km (200 miles) north of the Libyan port of Benghazi and more than 400 km away from Malta or Italy's southern island of Sicily.
Italian NGO Emergency said on Thursday its Life Support ship and the Ocean Viking, another charity vessel, had unsuccessfully looked for the missing boat for 24 hours, but found no sign of any shipwreck.
According to Reuters, a spokesperson for Emergency said on Friday the search was still on, adding that the migrants might have been picked up by another boat or may have managed to fix their engine and continue sailing towards Sicily.
The Italian Coast Guard reported on Thursday the rescue of 423 and 671 migrants in two separate operations in Italian search and rescue waters, and Alarm Phone said they were unrelated to the missing boat.
The Italian coast guard had no immediate comment.
In a separate incident, German charity SOS Humanity said 27 migrants were picked up at sea by an oil tanker and illegally taken back to Libya.
Under international humanitarian law, migrants cannot be forcibly returned to countries where they risk serious
ill-treatment, and widespread migrant abuse has been extensively documented in Libya.
Performance Shipping, the Greek company that owns the P. Long Beach tanker allegedly involved in the incident, did not immediately respond to a request for comment sent via the company's website.
