Authorities in Greenland are assisting local residents after an earthquake off the Arctic island's west coast triggered a tsunami. The earthquake struck late Saturday at a magnitude of about 4.0, according to the Geological Survey of Denmark and Greenland (GEUS), Danish news agency Ritzau reported. The quake struck about 30km north of the island of Nuugaatsiaq, home to about 100 people. Greenland public broadcaster KNR said 39 people had been evacuated from Nuugaatsiaq. Flooding was also reported near other settlements along the coast. A police spokesman in the Greenland capital Nuuk told dpa he had no information on whether people were injured. Local residents in the affected area were advised to avoid low-lying areas. Helicopters and vessels have been dispatched to the area.