<P> As a normal precaution, authorities declared a red alert, closed the road between La Fortuna and Tilarán, which runs around the north side of the volcano, and evacuated approximately 450 people (mostly tourists) from the immediate area, including several hotels and tourism oriented businesses . There were no reports of injuries caused by the volcanic activity . </P> <P> At 5: 20 p.m. on Tuesday the volcano was still discharging material, but activity had decreased significantly . </P> <P> The eruptions of May 7, 1998 damaged two square kilometers and destroyed a 400 by 100 meter area of green forest in the vicinity of Arenal Volcano . A fissure, 500 meters long and 10 meters deep, was opened up in the wall of the crater and all the material slid down the side of the volcano . </P> <P> During this day 23 eruptions were reported, between 1: 05 p.m. and 7: 00 p.m., and thereafter the volcano returned to its normal state . Authorities reported no unusual behavior and the national park was reopened the same week . Local seismologists investigate the activity of the volcano and park rangers continue to vigorously enforce the safety perimeter . </P>

When was the last time the arenal volcano erupted