Quito, Nov 4 --(EFE)-- The Ecuadorian Geophysical Institute said Thursday that
 25 minor explosions occurred in the Tungurahua volcano and more than 3,000
 weak tremors were recorded in Guagua Pichincha over a 24-hour period.

 An increase in the internal energy within Tungurahua could cause a large
 explosion of ash, lava and gas within days or a few weeks, warned Hugo Yepes,
 director of the Institute.

 The 5,016-meter (16,500-foot) Tungurahua is located in the central part of Ecuador
 and has been producing clouds of ash and glowing rock every day for more than a
 week.

 Scientists call these explosions ``Strombonian'' and warn that these are a
 preamble to a ``grade three'' eruption on an international seven-point scale.

 Civil Defense already evacuated 25,000 people who live near the volcano and will
 evacuate another 2,000 in settlements slightly farther from the crater.

 Meanwhile, the Institute will monitor Guagua Pichincha for five days to gain a
 better understanding of its current behavior.

 Th volcano is some 180 kilometers (112 miles) north of the Tungurahua and lies to
 the east of Quito, which would not be directly affected by a possible major
 eruption.

 According to the Geophysical Institute, earthquakes were more frequent Thursday
 than Wednesday and it estimates that in the next five days these will decrease
 prior to an explosion.

 Yepes said the decrease in tremors is an indicator of an explosion, adding that if
 the latter occurs, the intensity will surely be greater than the ones Oct. 5 and 7,
 when it spewed tons of ash over the capital and produced a mushroom cloud.