A magnitude-6.4 earthquake struck early Monday off the northern coast of Puerto Rico and was felt throughout the island, but caused only minor damage.

The temblor occurred shortly after midnight Sunday at a depth of 28 kilometers (17.4 miles) and was followed by dozens of aftershocks.

The epicenter lay 57 kilometers (35 miles) north of the coastal town of Hatillo, according to the U.S. Geological Survey.

Though officials did not issue a tsunami warning, some residents of greater San Juan and other areas on Puerto Rico's north coast jumped in their cars and drove inland.

"My first reaction was to look at the security cameras thinking to look for water from a tsunami coming in, because in that case I would have had to sound the alarm," Juan Otero, a security guard at a seaside community in the capital's upscale Condado neighborhood, told Efe.

"No damage has been reported in San Juan," capital Mayor Carmen Yulin said on Twitter.

The Puerto Rican government has yet to issue an official statement about the earthquake, which nearly coincided with the fourth anniversary of the massive Jan. 13, 2010, temblor that caused some 300,000 deaths in nearby Haiti. EFE