Chile Sunday commemorated the first anniversary of a devastating 8.8-magnitude quake hitting southwestern Chile on Feb. 27, 2010, with President Sebastian Pinera appealing for national unity during the reconstruction process.

In Bio Bio region's Cobquecura, the quake's epicenter, Pinera attended a ceremony to mark the disaster, which killed more than 500 people, left 800,000 homeless, and caused some 30 billion U.S. dollars in economic damage.

Hundreds of Cobquecura residents held candles and marched to the main square of the town, where Catholic bishop Carlos Pellegrini headed a mass.

The quake struck this South American country at 3:34 a.m. local time (0734 GMT) one year ago.

At 3:33 a.m. local time (0733 GMT), all participants observed a one-minute silence to commemorate the precise occurring of the quake.

After this, a marine played a funeral tune with a trumpet for 2 minutes and 45 seconds, the time the earthquake lasted.

During a speech at the ceremony, Pinera said, "I want to remind all Chileans at this time of adversity and challenge, and we need to unite more than ever."

He said his government has finished more than half of the reconstruction work, and will complete the house building task by the end of 2012.

Currently, some 800,000 homeless people are still living in temporary houses in the quake-hit region.

There were also commemorative ceremonies in Constitucion and Talcahuano of Bio Bio region.

In Constitucion, inhabitants dressed in black and attended a mass on Orrego Island, where one year ago many camping people were killed by a tsunami triggered by the quake.

In Talcahuano, many fishermen toured the coast to remember those killed there.

The opposition parties accused the government of slowness and lack of transparency during the reconstruction, which was flatly denied by President Pinera.

"Now it is time for unity and not division, time for great and not small things. Things can always be done better, but I want all Chileans to know our country has done all things possible to rebuild," said the president at the ceremony.