At least 217 people were killed after an earthquake of 7.1 magnitude on the Richter Scale struck central Mexico on Tuesday night, flattening buildings and crushing cars and people, The Guardian reported. The toll was earlier at 248, but the country’s civil defence chief lowered the number later.

President Enrique Peña Nieto said more than 20 children had died after a three-storey school building crumbled in Mexico City. Nearly 30 more children are still missing, local media reported.

The tremor hit the country as earthquake drills were being carried out in Mexico City on the anniversary of the 1985 quake, which killed around 10,000 people. While some reports said that this saved many people, others said that residents thought the earthquake alarms they heard were part of the drills, according to the BBC.

Some reports said the earthquake may have triggered an eruption of the Popocatépetl volcano. A church on the slopes of the volcano collapsed and killed 15 people, Puebla state’s Governor Jose Antonio Gali said.

The epicentre was near Raboso town in Puebla, about 122 km southeast of Mexico City, at a depth of 51 km, the US Geological Survey said. Officials said that at least 86 people were killed in Mexico City, and more than 70 had died in the state of Morelos, just south of the capital. More than 40 people died in Puebla.

The quake hit around 1.15 pm local time and sent thousands of residents to the streets, most of whom remained outdoors fearing aftershocks. About 2 million people in Mexico City are without electricity, and phone lines are also down.

This was the second major earthquake to hit the earthquake-prone country in as many weeks. On September 7, an earthquake of magnitude 8.1 struck off the southern coast of Mexico, killing at least 90 people.