The volcano, located about 180 km south of the capital Quito, underwent three emissions early Tuesday after a massive eruption on Monday, with ash columns reaching as high as 3,000 meters, said the country's Institute of Geophysics in a report.
No one was reported killed or injured in the latest eruption, though intense rumbling sounds and big explosions terrified people living in the vicinity, and some were evacuated temporarily.
"We were ordered to leave home at night after the eruption on Monday. It has been nearly 24 hours since then," said Miguel Freire, one of the inhabitants there.
The authorities have asked the rescue force to stand by for possible evacuation when necessary, though researchers said the volcano in the Andes mountains tended to be less active in the future.
The eruption would probably lead to heavy crop loss due to the large clouds of ash spewed by the volcano, said local official Jaime Alvarez in the city of Penipe.
The Tungurahua, around 5,000 meters high, came back to life in 1999 and is regarded as one of the most active volcanoes in Ecuador. After six months of relevant calm, it seemed to have started a new round of eruptive process since December, researchers said.