
The 17 bodies were found on three inflatable dinghies, from which over 300 other migrants were rescued alive, the Italian Navy said on Twitter.
Friday's rescue operations were led by the Italian coastguard, and involved German and Irish naval ships working under the auspices of the EU's Frontex border agency.
A similar international maritime mission off the coast of Sicily on Thursday resulted in the rescue of over 700 migrants from Libya in six boats.
So far, the busiest days this year have been on April 12 when 3,791 migrants were rescued and the May 2 rescue of 3,690 people.

New statistics gathered by IOM confirm 2015 appears to be "an even deadlier year than 2014," when nearly 3,300 migrants perished trying to enter Europe. While last year the number of migrants dying in all Mediterranean crossings from January to April was 96, this year's toll is an estimated 1,770 so far through to April 30, IOM said.
EU ministers have approved plans for a military operation to fight people smugglers in the Mediterranean. Proposals to destroy traffickers' boats in Libyan waters still need UN approval, however. The European Commission plans to make the rest of the 28-nation EU share the burden of frontline, brunt bearing states such as Italy, Greece and Malta, although some countries, the UK among them, are against the plan.
Comment: A proposed solution to this terrible, ongoing humanitarian crisis is discussed in this article: Problem solved: NATO and EU want to bomb refugee terrorists they created