Chilean authorities have issued a tsunami warning and ordered evacuations after a magnitude 7.4 earthquake struck off the southern coasts of Chile and Argentina.

The Chilean National Service for Disaster Prevention and Response issued a “red alert” on Friday for coastal areas in its southernmost Magallanes region and the country’s Antarctic territory due to the tsunami risk.

In a post on its website, the agency said hundreds of people had been evacuated from a handful of communities, including the town of Puerto Williams.

“The National Disaster Prevention and Response System continues to assess the impact on people and damage to infrastructure and basic services,” it added.

No damage or casualties have been initially reported.

The earthquake struck Drake Passage between Cape Horn and Antarctica at a depth of just 10km (six miles), the United States Geological Survey said.

Magallanes is Chile’s largest and southernmost region and one of its least populated. According to government figures, in 2017, the population totalled about 166,000 people.

Chilean President Gabriel Boric said all of the country’s resources were available to respond to the quake.

“We call for evacuation of the coastline throughout the Magallanes region,” he wrote in a social media post. “At this time, our duty is to be prepared and heed the authorities.”

Videos on social media showed people calmly evacuating as sirens blared in the background.

Chile’s Hydrographic and Oceanographic Service (SHOA) estimated that waves will reach bases in Antarctica and cities in Chile’s extreme south in the coming hours.

Meanwhile, in the Argentinian city of Ushuaia, considered the world’s southernmost, local authorities suspended all types of water activities and navigation in the Beagle Channel for at least three hours.

“The earthquake was felt primarily in the city of Ushuaia and, to a lesser extent, in towns across the province,” the local government reported. “In the face of these types of events, it is important to remain calm.”