WASHINGTON (Reuters) - A magnitude 6.4 earthquake struck northern Argentina early on Monday, the U.S. Geological Survey said.

The quake occurred at 2:07 a.m. local time (1.07 a.m. EDT) and was centered 72 miles east-southeast of Santiago del Estero, the USGS said.

Police in the town said there were no immediate reports of injuries or damage from the quake, which was upgraded from an initial 6.3.

(Reporting by Hugh Bronstein; Editing by John Stonestreet)