BANGKOK (Reuters) -Signs of life were detected in the ruins of a skyscraper in Bangkok on Monday as efforts intensified to find people trapped three days after a massive earthquake in Southeast Asia that killed at least 2,

The Chinese embassy in Bangkok has called for full cooperation with the Thai authorities’ investigation into the State Audit Office collapse.

Large quakes produce shaking at a variety of frequencies. Some waves can travel hundreds of miles, and are amplified by local geological conditions.

Poorly paid migrant workers from Myanmar have built many of Bangkok’s glittering high-rises, including the one that collapsed in Friday’s earthquake.

Officers questioned four Chinese men who were found removing 32 files from containers behind the collapsed building, a police official said.

Rescuers in Bangkok are racing to find survivors in the rubble of an under-construction high-rise that came crashing down. At least 15 people have died in the collapse and more than 70 are missing.

Several people were killed in a building collapse and dozens more were missing as of Friday evening in Thailand, the authorities said.

A Chinese-backed contractor is facing an investigation over the collapse of a 33-floor skyscraper in Bangkok in Friday’s earthquake.

The governor of Bangkok says authorities are investigating why a high-rise building under construction collapsed during an earthquake that otherwise caused limited damage in the Thai capital.