Interior Minister Angelino Alfano canceled his appointments Thursday and headed to Italy's southernmost island to oversee the rescue operations.
Pope Francis, who visited Lampedusa in July, quickly sent condolences.
It was the second shipwreck this week off Italy: On Monday, 13 men drowned while trying to reach southern Sicily when their ship ran aground just a few meters (yards) from shore.
Hundreds of migrants reach Italy's shores every day, particularly during the summer when seas are usually calmer.