BOSTON (AP) -- The parents of a Massachusetts woman say she is safe after she and a friend escaped from a ferry that sank off the coast of Tanzania, killing at least 31 people.

Hilary Strasburger of Somerville called her parents at their Maine vacation home and told them she and another American were on the top deck of MV Skagit when strong winds sank it Wednesday. More than 100 passengers are still missing.

Carrie Strasburger said Thursday that her daughter told her water pressure prevented people from escaping. She and her friend got out after someone pushed out a window.

They spent two hours in a life raft before a rescue boat came.

Strasburger was visiting an orphanage in in the East African nation of Uganda, then went on vacation in neighboring Tanzania.