By the CNN Wire Staff

updated 5:16 PM EDT, Tue March 20, 2012
Mexico City (CNN)
-- A strong earthquake rattled residents in southern Mexican resort towns and the nation's capital Tuesday, but there were no immediate reports of serious damage or injuries.

The U.S. Geological Survey reported the quake had a magnitude of 7.4.

The epicenter was about 15 miles (25 kilometers) east of Ometepec, Guerrero, the USGS said, and its depth was about 12.4 miles (20 km).

More than an hour after the quake, residents of town were feeling aftershocks, said Francisca Villalva Davila, the city's comptroller.