QUITO, Oct. 23 (Xinhua) -- The government of Ecuador on Sunday declared a yellow alert (moderate risk) in areas near the Cotopaxi volcano amid increasing seismic activity.

The volcano, at 5,897 meters above sea level, is the second highest summit in the country.

The yellow alert was adopted based on a report showing an increase in volcanic activity since Oct. 21, when Cotopaxi registered a tremor, which was the most activity observed since 2015, said the Ecuadorian Secretariat for Risk Management in a statement.

At present, nearby residents can see gas and water vapor hovering 500 meters above the crater, and an ash column as high as 2,353 meters. Authorities thus suspended visits to the volcano.

The last major eruption of the volcano occurred on June 26, 1877. In 2015, the volcano exhibited new activity but did not erupt.