A boat carrying some 220 migrants has issued an SOS call to Malta and Italy, according to the Italian media.
The boat is taking in water and is at risk of sinking, the migrants reported by satellite phone.
The boat, according to the migrants, is 80 miles north of the Libyan coast.
The Italian media said the Maltese authorities had reported that they were monitoring the situation but the boat was not yet in Maltese waters. Italian rescue boats were dispatched to the area.
However, official sources in Malta said the boat was 27 miles south of Malta's search and rescue zone. A Maltese patrol boat was deployed to the area but did not find the boat.
Meanwhile, the migrants' influx into Lampedusa is continuing, with six boats carrying some 1,000 migrants detected.