YANGON: A candidate for Aung San Suu Kyi's opposition was wounded by a sword-wielding attacker while canvassing in Yangon, his party said Friday, as tensions rise just over a week before Myanmar holds key elections.

Naing Ngan Linn, a sitting MP for the National League for Democracy, suffered injuries to his head and arms when he was set upon late Thursday as his campaign group toured a township in his constituency.

"(The man) started punching an NLD member. Then people tried to make him go home because he was drunk. But he came back with a large knife," said Thet Htar Nwe Win, another NLD candidate, who witnessed the incident.

"Naing Ngan Linn tried to stop him... that's why he sustained many injuries," he told AFP, adding several other men had attacked the group but were unarmed.

It was not clear what motivated the assault, which left three other NLD members with minor wounds. Thet Htar New Win said at least two people had been arrested.

Political tensions are high in former junta-run Myanmar, where Suu Kyi's opposition is contesting nationwide elections for the first time in a quarter of a century.

The party is likely to make major gains in the vote, potentially tipping the balance of power away from the military and its ruling party allies for the first time in generations.

Myanmar's elections are set to crown more than four years of reforms that have seen the nation open its doors to the world under a quasi-civilian regime that replaced junta rule in 2011.

Campaigning has largely been calm, although the NLD has complained that its rivals have used religion as a political tool.

Those concerns carry weight in a nation that has seen waves of anti-Muslim violence in recent years. NLD spokesman Nyan Win told AFP that the attack on Naing Ngan Linn was "the worst case during our campaign so far" and called for immediate action from police.

His wife Khin Sandar Win said he suffered wounds on his forehead, hands and wrists and had undergone an operation late Thursday. His condition was not life threatening.

"It happened in front of my eyes. The man who attacked was shouting abusive words against NLD when our vehicle arrived," she told AFP.

The attack comes just days before Suu Kyi is due to speak at a major rally in Yangon at the culmination of weeks of energetic campaigning around the country by the veteran activist.

A spokesman for the party who was overseeing preparations at the rally site Friday said there would be "normal" security for Sunday's event.

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