A blast hit a busy market in Myanmar's conflict-torn Rakhine state on Thursday, killing and wounding civilians, the country's junta and an ethnic rebel group said, blaming each other for the attack.

Clashes have rocked Myanmar's western Rakhine state since the Arakan Army (AA) attacked security forces in November, ending a ceasefire that had largely held since the junta's 2021 coup.

The AA is one of several armed ethnic minority groups in Myanmar's border regions, many of whom have battled the military since independence from Britain in 1948 over autonomy and control of lucrative resources.

A junta naval vessel shelled the popular "Korea port" market in state capital Sittwe early Thursday, the AA's political wing said in a statement, killing 12 civilians and "critically" wounding 31 others.

Fifty others suffered minor wounds, it said, accusing the junta of targeting the civilian population.

The junta said the blast was a result of "careless heavy artillery shooting" by the AA, which had killed and injured a number of local people. It did not say how many.

Local media said seven people had been killed and around 30 wounded.

AFP was unable to verify either account.

Junta troops hold Sittwe but in recent weeks AA fighters have made gains in surrounding districts.

Communication with the coastal town is extremely difficult, with most mobile networks cut.

Fighting has also spilled over into neighbouring India and Bangladesh.

Earlier this month at least two people were killed in Bangladesh after mortar shells fired from Myanmar during clashes there landed across the border.

Earlier this month India told its citizens still in Rakhine to leave immediately.

AFP has contacted a junta spokesman for comment.