SEOUL ? A powerful 6.7-magnitude earthquake struck off North Korea's border with China and Russia Thursday but there were no immediate reports of damage and no tsunami warning was issued, seismologists said.

The quake struck at 10:13 a.m. (0113 GMT), 111 kilometers (69 miles) northeast of Chongjin at a depth of 562 kilometers, the US Geological Survey said.

The Hawaii-based US Pacific Tsunami Warning Center said the quake did not generate a destructive tsunami.