Rescue operations continue in Myanmar and Thailand nearly 72 hours after a powerful earthquake struck the central part of Myanmar on Friday. The chance of survival in a disaster is said to drop sharply after the crucial 72-hour mark.

The magnitude 7.7 earthquake caused extensive damage in Myanmar's second largest city of Mandalay and capital Naypyitaw.

The country's military leader Min Aung Hlaing says the quake has claimed about 1,700 lives and injured some 3,400 people.

Rescue workers are searching for those believed to be trapped in collapsed buildings.

In the central city of Mandalay, a large condominium building was severely damaged with its lower floors flattened.

Local officials say a Japanese national who lived in the condo is unaccounted for. Japan's Foreign Ministry has asked Myanmar authorities, via its embassy in the country, to search for and rescue the Japanese national.

Damage has also been reported in neighboring Thailand. A high-rise building under construction collapsed in the capital Bangkok.

Thai authorities say at least 11 people were killed and more than 70 others remain unaccounted for.

Search and rescue operations continued overnight using large cranes and excavators as the 72-hour mark comes on Monday afternoon.