Two New Earthquakes Shake Southern Mexico, Already Coping With Disasters

Two more earthquakes shook southern Mexico on Saturday, further rattling a country still coming to grips with the devastation from stronger temblors earlier this month.

A 6.1 magnitude earthquake Saturday morning was centered in Oaxaca state near Matias Romero, a town about 275 miles southeast of Mexico City, the US Geological Survey said. Roughly speaking, the epicenter was between the centers of this month's two more violent earthquakes -- the 7.1 magnitude temblor that hit Tuesday closer to the capital, and the 8.1 magnitude quake that struck September 8 off the southern Pacific coast, near Chiapas state.

A 4.5 magnitude quake hit Oaxaca at 7:06 p.m. ET. That temblor occurred at a depth of 8.9 kilometers, according to initial readings by USGS.

Mexico City did not appear to have sustained significant damage in the earlier and stronger of Saturday's two quakes, said the country's office of the secretary of public security.

Warning sirens sounded in Mexico City after the morning quake was detected, interrupting rescue operations at some of the dozens of buildings that collapsed from Tuesday's earthquake.

A 6.1 magnitude quake can produce strong shaking and considerable damage to poorly built structures and slight to moderate damage in better-constructed buildings, the USGS says.

The earlier major quakes killed hundreds of people and turned buildings into dust and debris in parts of Mexico. More than 300 people have been reported killed in Tuesday's quake; nearly 100 reportedly died in the September 8 temblor.