(CNN) -- At least 17 people were killed when a ship carrying migrants sank Monday about 100 miles off southern Italy, the Italian navy said Tuesday. Just over 200 other people who'd been on the ship were rescued, the navy said. The incident came a day after a boat carrying illegal migrants sank off the coast of Tripoli, Libya, killing at least 40 people, according to an account from Libya's Interior Ministry. Southern Italy -- especially tiny Lampedusa, which is the closest Italian island to Africa -- is a frequent destination for refugees seeking to enter European Union countries from Africa. Migrants often pack into unseaworthy and ill-equipped boats, and shipwrecks off Italian shores are common.
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NEW: U.N. refugee agency is dismayed by rising migrant death toll in Mediterranean
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About 200 people rescued from boat in Mediterranean on Monday, Italian navy says
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Deadly shipwreck came a day after a boat sank off Libya, killing at least 40
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The Italian military rescued about 2,000 migrants in five days alone, navy says
It praised rescue efforts by the @placeholder and Libyan authorities, as well as private boats, but said more still needs to be done.