Sri Lankans crowded polling stations Tuesday to elect their president, choosing between two Sinhalese war heroes who have both promised to bring development to the South Asian country.

Sri Lankan President Mahinda Rajapaksa prepared to vote in the presidential elections in Medamulana, about 220 kilometres southeast of central Colombo, on Tuesday. (Dinuka Liyanawatte/Reuters)

President Mahinda Rajapaksa and his former army leader, retired general Sarath Fonseka, have also promised to lead Sri Lanka's rebuilding effort after a 25-year-war with the Tamil Tigers, a political and military group that had been fighting for an independent homeland since the 1970s.

Several explosions were heard in Jaffna, a predominantly ethnic Tamil city, before polls opened.

Election monitor Paikiyasothy Saravanamuttu said one blast was a grenade attack on the office of a ruling party organizer. However, an opposition Tamil lawmaker accused the military of firing artillery shells into the sea to dissuade voting among Tamils, who were expected to lean toward Fonseka.

Military spokesman Brig. Udaya Nanayakkara denied the military fired artillery.

There were no reports of major violence by the time polls closed in the afternoon.

Several explosions were heard in Jaffna, a predominantly ethnic Tamil city in northern Sri Lanka, before polls opened on Tuesday morning. (CBC)

The opposition said it feared the government would try to steal the election and, in a sign of possible irregularities, Fonseka said his own name didn't appear on the voter registration list. The electoral commission said that would not affect his candidacy.

Strong following among Sinhalese

Though there have been no reliable polls, both candidates appear to command strong Sinhalese followings.

Rajapaksa had campaigned on his war record and his promises to bring development to the nation and branded Fonseka a potential military dictator.

Fonseka, who also pledges an economic renaissance, accused Rajapaksa of entrenched corruption and promised to trim the powers of the presidency and empower parliament if elected.

Tamil marginalization remains

But neither has presented a detailed plan to resolve the underlying ethnic tensions — and Tamil complaints of marginalization — that sparked the rebels' separatist insurgency in the first place.

Former Sri Lankan army commander Sarath Fonseka, who is challenging the president, attended a news conference on election violence in Colombo on Monday. (Andrew Caballero-Reynolds/Reuters)

While voting among the Sinhalese majority appeared strong, there was less enthusiasm among Tamils, especially in their traditional northern bastions where the most intense fighting drove hundreds of thousands from their homes.

Though it has been just eight months since Rajapaksa and Fonseka declared victory in the war against the rebels, many voters were more focused on the stagnant economy than the newfound peace.

"Life is difficult, the cost of living is high. We need a change of government to stop corruption," said Pathirannnehelage Priyalal, a 40-year-old businessman in the town of Gampaha, north of Colombo, who said he voted for Fonseka.

"There has been no relief even after the war and if this government remains, even finding food will be difficult," he said.