TUNIS, Tunisia (AP) — At least two migrants died and 21 have disappeared after their boat capsized Sunday off the Tunisian coast in the Mediterranean Sea, Tunisian officials said. Seven others were rescued.

According to the spokesman at the court in Mahdia, a Tunisian port, coast guards were alerted by a survivor. Ferid Ben Jha told The Associated Press that all 30 migrants onboard were Tunisian citizens who wanted to cross the Mediterranean and reach Italy.

He said prosecutors have opened a criminal investigation into human smuggling.

A coast guard official, who spoke on condition of anonymity because he was not allowed to talk publicly, said the shipwreck was probably due to bad weather and the boat being too small, with a capacity estimated to be only up to six people.

Several Tunisian ships were involved Sunday in an ongoing search-and-rescue operation at sea, he said.

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