A 6.3-magnitude earthquake struck Tuesday off Mexico's Pacific coast, not far from the border with Guatemala, the US Geological Survey said. The epicenter of the quake, which struck at 2243 GMT at a depth of 44 kilometers (27 miles) was located 90 kilometers (56 miles) from Tapichula in Mexico's Chiapas state, and 265 kilometers from Guatemala City, the USGS said. An 4.6-magnitude aftershock occurred less than 15 minutes later. A quake with a magnitude of 4.5 struck the same spot earlier in the day. Also on Tuesday, a 5.7-magnitude quake struck farther north off Mexico's Pacific coast, about 200 kilometers southwest of the capital Mexico City. There were no reports or casualties or major damage. That was the fourth quake felt in the capital in little more than a month, since a major March 20 tremor that left two dead and about a dozen injured.