A bomb blast in a busy neighbourhood of Myanmar's commercial hub Yangon killed one person and injured nine others on Tuesday, police and junta authorities said.

The Southeast Asian country has been in turmoil since a military coup that ousted Aung San Suu Kyi's civilian government, with anti-junta groups clashing regularly with the military.

The blast occurred around 3:20 pm local time (0850 GMT) near a bus stop in Yangon's Downtown district, a police source said, requesting anonymity.

Pictures published by local media showed passers-by tending to several injured people as they lay on the ground, and what appeared to be blood on the pavement.

A local volunteer paramedic who arrived on the scene shortly after the explosion told AFP his team had taken two seriously injured people to hospital.

Security forces later found an unexploded grenade near the site of the blast, the police source said. 

One man in his 30s died from his injuries after being taken to a hospital and nine others were receiving treatment, the junta's information team said in a statement.

The blast came from a "homemade mine", it said, blaming the attack on "People's Defence Force" fighters -- groups that have sprung up to fight the military's bloody crackdown on dissent.

No group has claimed responsibility for the attack.

A shadow government dominated by lawmakers from Suu Kyi's ousted party, and which is working to reverse the coup, condemned the blast.

"We strongly condemn this terrorist act targeting civilians," its defence ministry said in a statement.

Turmoil 

Across the country, there are almost daily killings of low-level junta officials or alleged informers, with details murky and reprisals from the military often following quickly.

In a separate statement, the junta said a bombing in Nawnghkio in northern Shan state had killed the head teacher of a primary school and injured seven others.

Local media also reported the blast, with images showing damaged walls and debris strewn across the floor.

AFP was unable to verify the reports. 

Most of the violence has occurred in rural areas, although anti-coup fighters have also targeted officials and infrastructure in towns and cities.

Last November, a top executive from Mytel -- a telecom venture between Myanmar's military and Viettel, itself operated by Vietnam's army -- was gunned down outside his Yangon home.

And in August, anti-coup fighters shot dead five policemen on a commuter train in Yangon.

More than 1,800 people have been killed and more than 13,000 arrested in the junta's crackdown on dissent since the coup, according to a local monitoring group.