VIDEO: Drone footage shows Mexico quake damage

Civil defence agency chief Luis Felipe Puente said at least 86 people died in Mexico City, 71 in Morelos state, 43 in Puebla, 12 in the State of Mexico, four in Guerrero and one in Oaxaca.

He gave no explanation for the lower toll after earlier reporting 248 confirmed deaths.

The update came as rescuers and volunteers dug through the rubble, looking for survivors of Mexico's deadliest earthquake since 1985.

Tuesday's magnitude 7.1 quake struck on the 32nd anniversary of a tremor that killed thousands and came just two hours after earthquake drills were held across Mexico to mark the date.

One of the most desperate rescue efforts took place at a primary and secondary school in southern Mexico City, where a wing of the three-storey building collapsed.

At the scene, journalists saw rescuers pull at least two small, sheet-covered bodies from the rubble.

The federal education department said late on Tuesday night that 25 bodies had been recovered from the school's wreckage, all but four of them children.