WELLINGTON, New Zealand — Water pipes were broken and fallen power lines lay on the ground today in Invercargill, the southern New Zealand city closest to an earthquake that struck off the coast the night before.

Prime Minister John Key was due to fly to Invercargill later today.

"All the feedback we've had so far is while it's been a large quake, certainly at this point no reported loss of life, which is fantastic, and no great reports of damage," Key told Radio New Zealand.

The 7.8-magnitude earthquake struck off New Zealand's west coast yesterday, generating a small tsunami. No injuries or major damage were reported.

The Pacific Tsunami Warning Center in Hawai'i warned that a tsunami was generated, but it later said the waves were less than 8 inches high, and the warning was canceled.

The quake's epicenter was 100 miles west of Invercargil, at a depth of 21 miles, the U.S. Geological Survey said.