The main opposition candidate in Ghana's presidential election was leading over his closest rival on Sunday but the ruling party said a second round was likely as preliminary returns showed the gap between the two had narrowed.

In counting for the parliamentary vote held on Thursday alongside the presidential vote, a local dispute over ballot boxes degenerated into ethnic clashes that left at least seven people dead in the northern town of Bawku, state radio said.

With results declared from just over half of the 200 constituencies, John Kufuor was ahead with 52.81 percent of the votes cast against 41.02 percent for his main challenger, Vice President John Atta Mills, following Thursday's general election.

The rest of the vote was split between five other candidates, most of whom conceded defeat on Saturday.

The Electoral Commission halted its piecemeal release of provisional results late on Saturday, saying it wanted to avoid confusion and would give the final results all at once on Sunday afternoon.

Kufuor's New Patriotic Party (NPP) said it was confident its candidate would clinch an outright victory.

``We have collected results from 192 constituencies and we are very confident,'' NPP Secretary-General Daniel Botwe told Reuters.

The ruling National Democratic Congress (NDC), however, said results in its possession showed Kufuor had won less than 50 percent of the votes cast.

``We are not conceding defeat. The tally that we have done indicates Kufuor is below 50 percent and that the presidential election is likely to go into a second round,'' Education Minister Ekwow Spid-Grabrah said on state radio.

``The NPP is not in a position to announce any victory at this stage.''

End Of Rawlings Era

The election marked the end of 19 years in power for President Rawlings, the West African country's longest serving leader since 1957.

A two-man run-off will be held within 21 days of the first round if no candidate grabs more than 50 percent of the vote.

Early returns, most of which came from NPP strongholds, had given Kufuor a lead of more than 10 percentage points over Mills. They also showed that several incumbent ministers lost their parliamentary seats to NPP rivals.

However, foreign electoral observers said the late release of results from the Volta and Northern regions, where the NDC draws the bulk of its support, had allowed Mills to partially close the gap and that a second round could not be ruled out.

``Given the NPP's poor showing in NDC strongholds, a few constituencies could just swing enough votes to require a run- off,'' said one European observer.

State radio, meanwhile, said at least seven people were killed after a dispute between NPP and NDC activists degenerated into ethnic violence in the northern town of Bawku, near the border with Burkina Faso.

It said several buildings had been set on fire and villagers had fled their homes.

Regional authorities imposed a dusk-to-dawn curfew on the town on Friday and extra security forces where deployed in the region.

Rawlings, who seized power with a military coup but won multi-party elections in 1992 and 1996, is due to step down on January 7 because of a constitutional two-term limit. He has pledged to respect the poll result.