It was 8:58 am Tuesday when the Volcan Poas blew its stack, blow smoke and ash some 1,000 meters (1 kilometer) high, reported the Observatorio Vulcanológico y Sismológico de Costa Rica (Ovsicori).
According to the report, the eruption continued well past 10 am as the emanation was maintained but at a less height, some 300 meters.
The Poas volcano erupted on April 1 and since it has gone through periods of extreme activity with periods of calm.
The activity of emanation of gases is constant, said the Ovsicori report, that, in conjunction with the National Seismological Network (RSN) indicated that seismic movements persist within the volcano.
Also, in the past week residents of places like San Pedro de Poás and Canoas, in Alajuela, reported an increase in the smell of sulfur.