Fears for Swiss twins, Alessia and Livia Schepp, 6, taken by their father (UPDATES) (VIDEO)

Police in Italy, Switzerland and France are hunting for a pair of 6-year-old Swiss twins whose father killed himself after abducting them.

Interpol issued an international Yellow Notice missing persons alert Saturday for Alessia and Livia Schepp, CNN reported. Such notices are distributed to police in Interpol's 188 member countries to help find missing people, especially children.

Police used tracker dogs and helicopters in an area around the railway station of Cerignola in southern Italy, where 43-year-old Matthias Kaspar Schepp threw himself under a train Friday. And late Monday, police were searching Lake Geneva by helicopter.

Alessia and Livia were reported missing Jan. 30 after their father took them from the home of his estranged wife, Irina, 44, in St. Sulpice, near Lausanne, Switzerland, Interpol said, driving them away in a car belonging to her.

State police said Canadian-born Schepp drove through Marseilles, France, on Tuesday, where Schepp had sent his estranged wife a letter saying he was desperate and could not live without her, Italy's Ansa news agency reported.

The agency quoted Swiss police as saying he had withdrawn large amounts of money from ATMs in the city.

French police say Schepp bought three tickets to catch a ferry from Marseille to Corsica but it's not clear whether they boarded.

Two days later, police in Bari, Italy, found the father's body, but there was no sign of the girls, who are blond and about 3 feet, 9 inches tall, Interpol said. When they were taken, Livia was wearing a green T-shirt, jeans, a violet ski jacket and Adidas sneakers. Alessia was wearing a T-shirt with red and white stripes, jeans, a brown jacket and black shoes.