A strong 6.0-magnitude earthquake shook southern Mexico and the nation’s capital early Saturday, prompting people to flee into the streets in the dead of night two days after a similar temblor.

A strong 6.0-magnitude earthquake shook southern Mexico and the nation's capital early Saturday, prompting people to flee into the streets in the dead of night two days after a similar temblor.

There were no immediate reports of damage or injuries following the quake, which struck as people slept at 2:36 am (0736 GMT).

The US Geological Survey, which monitors earthquakes worldwide, said the epicenter was seven kilometers (four miles) west of Tecpan de Galeana in the southern state of Guerrero, with a depth of 35 kilometers.

Mexico's National Seismology Service had measured it at 6.3 and later revised it down to 5.9, closer to the USGS's assessment.

"The states of Guerrero, Morelos, Oaxaca and the Federal District (Mexico City) have not reported any damage," said national civil protection coordinator Luis Felipe Puente.

The earthquake rattled people out of their sleep and tormented those awake at bars.

"The bed's movement woke me up. I grabbed the kids and we got out running," said Rosalia Leyva, a 49-year-old lawyers who fled her Mexico City apartment.

Adriana Mendoza, 21, was outside a bar in downtown Mexico City when it happened.

"It felt horrible. I almost fell and I haven't even had much to drink," she said.

Puente said the earthquake was the 22nd aftershock following a 6.4-magnitude temblor that hit the country on Thursday.

Thursday's earthquake was centered 15 kilometers from Tecpan de Galeana, causing a bridge to collapse in Guerrero but sparing the country from major damage or injuries.

The new temblor came three weeks after a powerful 7.2-magnitude earthquake shook the capital and the Pacific resort of Acapulco on April 18, causing panic but no major damage.

Mexico City is sensitive to distant earthquakes because it was built over soft soil from a drained lake that magnifies their effect.

In 1985, thousands of people were killed in the capital when buildings collapsed after an 8.1-magnitude temblor struck the Pacific coast.