At least 32,000 homes were damaged by an earthquake in southern Mexico, but no one was killed and just 13 people were injured, authorities said.

Angel Aguirre, governor of the southern Guerrero state, said Wednesday that preliminary reports indicated that 30,000 homes had been damaged, with 800 of them destroyed completely, by Tuesday's powerful 7.4-magnitude earthquake.

He added that a shelter had been set up for some 200 displaced families.

Gabino Cue, governor of the neighboring Oaxaca state, reported that 2,000 homes had been damaged as well as several public buildings.

The damage was more limited in Mexico City, but Mayor Marcelo Ebrard said some 250,000 people were without running water because of severed pipes.

The earthquake -- with its epicenter south of the Pacific resort of Acapulco -- was the most powerful to hit the country since one in 1985, which destroyed entire neighborhoods of the capital and killed thousands.

More than 40 aftershocks, some of up to 5.0 magnitude, shook the Mexican capital and southern areas in the aftermath of Tuesday's earthquake, according to the National Seismological Service.