A powerful earthquake that struck Myanmar at the weekend has left 38 people dead or missing, the Red Cross said Tuesday as a new tremor rattled the government's showpiece capital Naypyidaw.

Hundreds of buildings were destroyed or damaged in Sunday's tremor, which sent terrified people running from their homes in the country's second-biggest city of Mandalay and surrounding villages.

At least 26 people were killed while 12 others are missing and about 230 were injured, Myanmar Red Cross Society deputy general secretary Aung Kyaw Htut told AFP.

"We have provided tarpaulin sheets to some of the victims and they are staying in temporary shelters," he said.

Previously the toll had stood at 13 dead, according to aid agencies.

The Red Cross said 251 houses were destroyed and 22 hospitals were damaged along with 137 religious buildings, 48 government offices and four schools.

A partially built bridge across the Irrawaddy River also collapsed, sending workers plunging into the water. Elsewhere several gold miners were buried.

An AFP team in the town of Thabeikkyin saw significant damage in the area near the epicentre of the quake.

Patients at the local hospital were being treated in tents outside amid fears buildings could be vulnerable to further tremors.

Authorities said on Monday they were providing help to victims but that communication problems made it difficult to assess the scale of the destruction.

A series of strong aftershocks has rattled the nation formerly known as Burma.

A 4.8-magnitude quake struck on Tuesday close to the government's showpiece capital Naypyidaw, according to the US Geological Survey, but there were no immediate reports of injuries or damage.

The initial jolt, which was felt as far away as the Thai capital Bangkok, came little more than a week ahead of a landmark visit by US President Barack Obama, as the West rolls back sanctions to reward dramatic political reforms.

Myanmar evening news carried a message of condolence to the victims from President Thein Sein on Monday.

"The government will strive to do its best in its relief and resettlement efforts in the area," the announcement said.

Earthquakes are relatively common in Myanmar. The USGS said six strong earthquakes, of 7.0-magnitude and more, struck between 1930 and 1956 near the Sagaing Fault which runs north to south through the centre of the country.

A strong quake near the Thai border in March 2011 killed more than 70 people.