Roads nearby were clogged with cars, jeeps and buses as thousands of terrified residents fled. Church bells pealed in the city of Angeles, adjacent to the air base, warning the more than 300,000 residents to seek shelter.; Reporters at the scene said the blast created a greenish-gray mushroom cloud "like an atomic bomb." They said they heard three blasts, and then a huge gray-greenish cloud burst from the crater, blocking out the sun.; There were no immediate reports of injuries. Philippine officials had evacuated about 19,000 villagers in recent days, but others stayed in scattered hamlets to tend to their animals and farms.; All telephone lines to Clark were down, and Armed Forces Television was unable to broadcast after at least three eruptions began at 8:51 a.m. (5:51 p.m. PDT), following two smaller emissions before dawn. Another eruption occured shortly before noon.; Scientists said the volcano had plenty of built-up magma and even more severe eruptions could come later.; "Most probably there will be more eruptions," said seismologist Julio Sabit.; Raymundo Punongbayan, director of the Philippine Institute of Vulcanology and Seismology, said everyone within a 12-mile radius should evacuate, or even within 18 miles, "to be safe."; 'Dark mushroom'; "The smoke is very thick, like a dark mushroom in the sky," Gus Abelgas, a reporter for ABS-CBN television, said in a broadcast from Botolan, near the volcano's western slopes. "It's just like what we saw in Hiroshima."; Other reporters described panic as people scampered for safety with their belongings and livestock.; Most of the Americans stationed at Clark were transferred to the Subic Bay Naval Base and were expected to remain there until the danger from the volcano was past.; In volcano's path; Punongbayan said the site where Clark is located was in the path of the volcanic flow from Mount Pinatubo during its last major eruption, in the 14th century.; Rollie Rimando, another volcanologist, said a major eruption could hurl debris and poisonous gases in a 12-mile radius, affecting both the base and parts of Angeles.; On Tuesday, a cloud of ash-laden steam rose up to 11,500 feet above the volcano but suddenly dissipated in the afternoon, only to revive again 20 minutes later. The area on the western slope of the mountain was covered in a thin layer of ash.; Ash began falling Monday on villages west of Angeles near the slopes of Mount Pinatubo, prompting authorities to close roads there. But Angeles police said Tuesday that no one was evacuating the area.; Some refused to go; A Philippine police major identified only as Major Reyes said he visited a remote settlement near the volcano after the blast and tried to talk a handful of residents into leaving. But they refused to abandon their livestock and water buffaloes, known as carabaos.; "If our carabaos die, we'll die with them," the officer quoted them as saying.; Col. Jose Balajadia, chief of the Philippine military's Clark Air Base Command, said Tuesday that troops remaining at the base had been issued gas masks in case ash falls over the installation.; At the Subic station, newcomers from Clark tried to sort out their finances, adjust to cramped living and otherwise cope with dislocation. Finance officers issued partial pay to personnel who had to leave before having a chance to go to the bank.; Smaller than anticipated; The eruption appeared to be smaller than that anticipated by Peter Lipman, a U.S. Geological Survey scientist in Menlo Park, who on Monday had said an eruption as massive as that of Mount St. Helens could occur any day.; After the eruption, Lipman tried unsuccessfully to telephone five USGS researchers monitoring the volcano from Clark Air Base.; In a conversation with Lipman half an hour before the eruption, the researchers said the volcano had had small eruptions earlier in the day. At the time of the phone call, they were planning a helicopter ride above the volcano to survey the size of the lava dome inside its crater.; There are about 21 active and 200 dormant volcanoes in the Philippines. The last major eruption was the Taal volcano, about 50 miles south of Manila, in 1965. That explosion killed about 200 people.; IFYOU'RE INTERESTED; The Filipino American Chamber of Commerce of Santa Clara County is raising funds for evacuating residents who live near the erupting volcano. Donations of any kind may be sent to the Filipino American Chamber of Commerce, Santa Clara County, 72 N. Fifth St., Suite 12, San Jose, Calif. 95112. Phone: 283-0833.
Mount Pinatubo erupted violently today and sent a cloud of smoke and ash 10 miles into the sky . Warning sirens and church bells sounded at Clark Air Base and surrounding communities . Terrified residents clogged roads in the vicinity of Pinatubo . U.S. and Philippine officials believed that more eruptions would occur and that everyone within 12 miles of Clark should evacuate immediately . Communications with scientists taking measurements on the mountain were unsuccessful . It is known that this team had planned to make a helicopter flight over the volcano to check the size of the lava dome inside the volcano .