(CNN) -- A 5.5-magnitude earthquake struck Mexico's Pacific coast in the southern state of Oaxaca Tuesday morning, near the city of Santiago Pinotepa Nacional, the U.S. Geological Survey reported.
There were no immediate reports of damage or injuries.
The quake hit at 7:04 a.m. (9:04 a.m ET), about 11 miles west-southwest of the city.
It happened at a relatively shallow depth of 4.7 miles, USGS said.
A second quake, registering a magnitude of 5.1, struck nearby a few minutes later, USGS reported.
The governor of Oaxaca, Gabino Cue, said a post-earthquake alert was activated, but said there were no injuries.
"As of now, we have no reports of damage," he added.