MATI, Philippines: A powerful 6.9-magnitude aftershock jolted quake-hit southern Philippines late Friday (Oct 10), triggering a fresh tsunami alert just hours after an earlier warning was lifted, authorities said.

The tremor struck at 7.12pm local time, prompting the Philippine seismology office to warn of "life-threatening wave heights" and urge coastal residents to "immediately evacuate to higher grounds or move farther inland".

The aftershock, the largest of at least 300 recorded so far, came fewer than 10 hours after the Pacific seaboard of the southern major island of Mindanao was rocked by a 7.4-magnitude temblor, killing at least six people.

In Mati city, close to the offshore epicentre of both quakes, the latest one knocked out power.

In Davao city, more than 100km to the west, a plane that had just landed with an AFP photographer on board shook as the crew prevented passengers from immediately deplaning.

They were later allowed to disembark, but were made to wait outside on the tarmac, instead of being taken inside the passenger terminal.

There were no immediate reports of casualties or damage from the aftershock.

PEOPLE SCREAMED AND RAN

The quake on Friday morning hit about 20km off Manay town in the Mindanao region at 9.43am, according to the United States Geological Survey.

Wes Caasi, a local official in Tagum city, northwest of Manay, told AFP that a government event at the city hall descended into chaos as panicked attendees fled. "They screamed and ran."

Confirming videos that circulated on social media, Caasi said she saw city workers scrambling down a metal Christmas tree they were decorating when the quake struck.

Other witnesses said they saw students and workers pouring out of schools, office buildings and shopping malls - although some footage shared on social media proved to be misinformation.

Many Visayan-language posts shared footage of a crane falling from a building and imagery of destroyed buildings, but AFP fact-checkers found both visuals predated the tremor.

So far, the tremors seem to have caused minor and scattered damage, according to witnesses.

More than 100 aftershocks were recorded, some reaching magnitude 5.0.

Dianne Lacorda, a police officer in Davao Oriental province, told AFP that power and communication lines wer...