St. John, U.S. Virgin Islands: A strong earthquake jolted people awake Saturday in the U.S. and British Virgin Islands and nearby Puerto Rico. There were no immediate reports of damages.

The magnitude 6.1 quake was the strongest to hit Puerto Rico in 20 years, according to Christa von Hillebrandt, director of the seismic network on the Mayaguez campus of the University of Puerto Rico.

The U.S. Geological Survey said the quake struck was centered about 70 kilometers (43 miles) northwest of Anegada in the British Virgin Islands.

Disaster officials in the British Virgin Islands and Puerto Rico said there were no reports of significant damage or injuries.

"At first I thought it was a big truck rolling by but then I realized the windows were closed," said British Virgin Islands government spokeswoman Sandra Ward.

The quake struck on the 90th anniversary of the worst temblor ever recorded in Puerto Rico, a magnitude 7.3 quake that killed 118 people in the western half of the U.S. Caribbean territory, Hillebrandt said.