Philippine marines and three gunboats surrounded a remote Muslim stronghold in the southern Philippines where separatists rebels were holding a Swiss tourist and his Filipina girlfriend. Hans Kunzli, 45, an interior decorator from Zurich, and Adelaida Gamboa were kidnaped Saturday from the resort island of Santa Cruz off the port city of Zamboanga. Military officials said there has been no contact with the kidnapers. Meanwhile, a 3-year-old Filipino-American girl abducted on Friday was released unharmed by suspected Muslim rebels, police said. Her parents own a rubber and coconut plantation on Basilan island across the strait from Zamboanga.