An earthquake struck late Saturday off Papua New Guinea's eastern coast with a preliminary magnitude of 7.5, the U.S. Geological Survey said.
The quake struck at 11:27 p.m. (6:27 a.m. Arizona time) and occurred at a depth of 19 miles, CNN reported.
It was centered 47 miles southwest of Panguna, Papua New Guinea.
After the quake, the Pacific Tsunami Warning Center issued a tsunami warning for Papua New Guinea and the Solomon Islands.
The incident is the latest in a series of seismic events in the region over the week. They began with magnitude-7.1 and magnitude-6.5 earthquakes on April 11, just to the northeast and southeast, respectively.
Since then, 45 earthquakes of magnitude-4.5 or greater have occurred nearby.
Earthquakes with magnitudes between 7.0 and 7.9 are classified by USGS as "major," second only to "great," which are 8.0 and up.
Also this past week, a powerful magnitude-7.2 earthquake shook central and southern Mexico on Friday, sending panicked people into the streets.
Some walls cracked and fell, but there were no reports of major damage or casualties.
The USGS said that quake at about 9:30 a.m. (7:30 a.m. Arizona time) was centered on a long-dormant fault line northwest of the Pacific resort of Acapulco, where many Mexicans are vacationing for the Easter holiday.