A powerful 7.6 magnitude earthquake has rocked northern Chile, just over 24 hours after an 8.2 tremor killed six people, destroyed 2,600 houses and led to mass evacuations.
A tsunami alert in Chile and Peru was again issued, but was later lifted after waves of 2.4ft (0.7 meters) hit coastal areas.
Chilean President Michelle Bachelet was among those evacuated on Thursday.
The quake is the strongest of several aftershocks following Tuesday’s tremor.
There have been no reports of damage from the latest quake.
The aftershock caused buildings to wobble and people to run into the streets in the port of Iquique, which was one of the cities hit by Tuesday night’s quake.
The latest quake was centred 23km (14 miles) south of Iquique.
The US Geological Survey said the aftershock had a depth of 20km (12 miles) and was felt across the border in southern Peru, where people in the cities of Tacna and Arequipa also fled buildings.
President Bachelet had earlier praised the “calm behaviour” of residents following Tuesday evening’s quake.
Nearly a million people were evacuated across the country after the authorities issued a tsunami warning.
“I think you have shown us all a tremendous example,” Ms Bachelet said during a visit to the worst affected areas.
Ms Bachelet declared two northern provinces – Arica and Parinacota, and Tarapaca – disaster areas.
Tuesday’s quake struck at 20:46 local time (23:46 GMT) about 86km (52 miles) north-west of the city of Iquique, a mining area,
“We are here to recognise the calm behaviour of the people of Iquique, who showed great civic responsibility, as did those of Arica,” said Ms Bachelet.
Fires destroyed some businesses in the area and fishermen found their boats sunken and damaged in Iquique harbour.
Ms Bachelet called on residents to “work together now” to repair the damage caused by the quake.
Waves of up to 2.1m (about 6ft) hit some areas.
Some 40,000 people in Tarapaca remain without power, said Ricardo Toro of Chile’s National Emergency Office (Onemi).
Hours after the first major earthquake, Chile’s army was deployed to Iquique after some 293 inmates escaped from a women’s jail.