(Updates with additional detail from Panama, Colombia authorities, aftershock)
May 24 (Reuters) - A magnitude 6.6 earthquake struck in the Gulf of Darien near the border of Panama and Colombia late on Wednesday, the United States Geological Survey (USGS) said, with tremors felt across both countries.
Nine minutes later, the USGS reported a 4.9 magnitude aftershock at the same location.
In Panama, civil protection agency Sinaproc said there had been no immediate reports of damages and they were monitoring the situation.
In the Colombian metropolis of Medellin, local officials said no damages had been reported.
Both quakes struck at a depth of 10 km (6.21 miles), the USGS said.
The U.S. Tsunami Warning System said there was no tsunami warning in place. (Reporting by Mrinmay Dey in Bengaluru, Eli Moreno in Panama City and Kylie Madry and Sarah Morland in Mexico City; Editing by Christian Schmolliger)