(Reuters) - A powerful 6.7 magnitude earthquake hit Guerrero state in southwest Mexico at 19:47 local time on Saturday (0147 GMT Sunday), the U.S. Geological Survey reported.

The earthquake rattled buildings in Mexico City and seemed to go on for an unusually long period. There were no immediate reports of damage but residents ran out of buildings and gathered in the streets outside.

The earthquake, centered 22 miles south of Teloloapan, was 40 miles deep, the USGS said.

The Pacific Tsunami Warning Center said a destructive tsunami was not generated by the quake.