The casualties, mostly Tunisians, drowned when their overcrowded boat sank after leaving the Kerkennah islands A total of 68 people were rescued from the vessel after it ran into trouble late on Saturday evening TUNIS: Tunisian Prime Minister Youssef Chahed has fired Interior Minister Lotfi Brahem, according to a government statement on Wednesday that gave no reason for the decision. Chahed had earlier said that at the weekend security guards had failed to stop a boat packed with 180 migrants that sank off the Tunisian coast killing at least 68 people. Earlier on Wednesday, Tunisia announced the sacking of officials accused of negligence over a shipwreck this weekend that killed at least 66 migrants. The casualties, mostly Tunisians, drowned when their overcrowded boat sank after leaving the Kerkennah islands off the coast of Sfax province. A total of 10 people were fired, among them national guard officials based in Sfax and others from the maritime unit in Kerkennah, the interior ministry said in a statement. A total of 68 people were rescued from the vessel after it ran into trouble late on Saturday evening. On Monday the International Organization for Migration said "at least 112 people" had died in the accident. Survivors have said the boat was packed with more than 180 people, which would mean dozens are still missing. The shipwreck is the deadliest in the Mediterranean since February 2, when 90 people drowned off the coast of Libya, according to the IOM. In recent months, Tunisia stopped about 6,000 migrants leaving its coast for Europe, a sharp increase from the few hundred prevented in the same period last year, an interior ministry official said on Wednesday. Human traffickers have increasingly moved operations to Tunisia since a crackdown by the coastguard in neighbouring Libya. "Since January 1 to the end of May 2018 we arrested about 6,000 migrants at our coasts compared to just a few hundred arrested in the same period last year," the official said, asking not to be named.Numbers are usually particularly low during the winter months when sea conditions are tougher. Most of the people on board that sank on Sunday were Tunisians trying to escape unemployment and an economic crisis that has gripped the North African country since the toppling of autocrat Zine El-Abidine Ben Ali in 2011. This year up to May 2, a total of 1,910 Tunisian migrants reached Italy, including 39 women and 307 minors - 293 of whom were unaccompanied - compared to only 231 for the same period in 2017, according to the U.N. migrant agency IOM. Overall, the number of migrants reaching Italy has fallen sharply since last July, when a major smuggling group in the Libyan coastal city of Sabratha struck a deal to halt departures under Italian pressure and was then forced out in clashes.