PORT MORESBY — An earthquake with a magnitude 7.8 was recorded off Papua New Guinea on Saturday, the U.S. Geological Survey said.The quake, at a depth of 10 km (6 miles), hit 68 km southwest of Panguna.The Pacific Tsunami Warning Center said a tsunami warning was in effect for Papua New Guinea and the Solomon Islands.An earthquake with a magnitude of 7.3 was recorded off Papua New Guinea's remote Bougainville Island on April 11, but there were no reports of damage.