Spain's maritime rescue service says a woman and a child died after the boat in which they and 30 other migrants were trying to reach Europe capsized in the Mediterranean Sea.

A service spokeswoman says a Spanish Navy unit stationed on Alboran island, halfway between Spain and Morocco, rescued 29 migrants after the boat overturned Tuesday afternoon.

She said a search for one missing migrant was continuing Wednesday.

The spokeswoman said a 10-year-old girl was found dead while the woman died later. It was not immediately known if the two related.

She said the boat was believed to have set sail from northern Morocco. There were no details on the migrants' nationalities.

The official spoke on condition of anonymity in keeping with service regulations.