SANTIAGO, Chile (AFP, REUTERS) - President Michelle Bachelet declared parts of northern Chile hit by an 8.2 magnitude offshore earthquake to be disaster zones.

Ms Bachelet said she would travel to the regions of Arica and Tarapaca on Wednesday, and send military officials to the areas to prevent looting and disorder. At least five quake-related deaths were reported by the interior ministry.

The quake had struck off the coast of Chile on Tuesday, triggering a tsunami, causing landslides that blocked highways and leading to five deaths.

Officials said the dead included people who were crushed by collapsing walls or were killed by heart attacks.

The U.S. Geological Survey said the quake was shallow at 12.5 miles (20.1 km) below the seabed and struck about 100 km northwest of the mining port of Iquique near the Peruvian border.

The government said it had no reports of significant damage to coastal areas, but around 300 prisoners took advantage of the confusion and escaped from a female penitentiary in Iquique, Interior Minister Rodrigo Penailillo said.

About 16 of the women were soon recaptured, Chile's investigative police said, while security forces fanned out through the area amid reports of power outages.

The Pacific Tsunami Warning Center said the quake generated a large tsunami with the biggest wave reported at 2.3 meters. The Chilean navy said the first big wave hit the coast within 45 minutes.

Iquique is a key copper exporting port, close to Chile's main copper mines. The area has been on high alert in recent weeks after an unusual number of tremors.

The government evacuated Chile's northern coast and a tsunami warning was issued for the Pacific coast of Mexico through Central and South America.

Chile is the world's No. 1 copper producer but key mining firms said there was no serious damage to their operations. The tsunami alert in the country would however go on for at least another six hours, the government said late on Tuesday.