MOUNT MERAPI, Indonesia — Indonesia's most dangerous volcano forced international airlines to cancel flights to nearby airports today, as fiery lava lit the rumbling mountain's cauldron and plumes of smoke blackened the sky.

Scientists warned that the slow eruption could continue for weeks, like a "marathon, not a sprint."

No casualties were reported in Mount Merapi's latest blasts, which came as Indonesia struggled to respond to an earthquake-generated tsunami that devastated a remote chain of islands last week. The two disasters in separate parts of the country have killed nearly 470 people and strained the government's emergency response network.

Indonesia, a vast archipelago of 235 million people, is prone to earthquakes and volcanos because it sits along the Pacific "Ring of Fire," a horseshoe-shaped string of faults that lines the Pacific.

Merapi has killed 38 people and prompted the government today to order airlines to choose routes circumventing the towering dark ash on takeoff and landing.

Malaysian budget airline AirAsia and Singapore's SilkAir responded by suspending several international flights to Yogyakarta and Solo, both within 20 miles of the crater.

Both airlines expected to resume operations soon.

MOSCOW — A 17-year-old foster child survived a 50-minute flight hidden in a plane's landing gear in Siberia, Russian investigators said today.The stowaway crawled into a space above the wheel of the Soviet-built Antonov An-24 turboprop at a small Siberian town's airfield on Saturday, said a statement issued by the Investigative Committee of the General Prosecutor's Office.Russian television said he survived the 50-minute flight to the regional center of Irkutsk in just a light coat, despite temperatures of minus 30 degrees Celsius. Investigators said the stowaway had fled a foster home, and the TV reports said he had robbed a nearby store before climbing inside the plane.He was being treated for frost bite, the reports said.