Ghana’s opposition leader on Tuesday warned President Nana Akufo-Addo against any attempt to steal this week’s election, as both sides claimed they were winning ahead of official results of the vote, largely deemed free and fair by observers.

The strong statement by opposition candidate John Mahama raised the temperature after Monday’s presidential and parliamentary polls in a country known for stability in a troubled region.

“Some of what is happening is unacceptable and Nana Akudo-Addo continues to show credentials that are very undemocratic,” Mahama told a hastily convened press conference in the capital Accra Tuesday evening.

“You cannot use the military to try and overturn some of the results in constituencies that we have won. We will resist any attempts to subvert the sovereign will of the Ghanaian people,” the 62-year-old former president said.

Information minister Kojo Oppong Nkrumah told a press conference — convened just minutes after Mahama spoke — that allegations of intimation by soldiers were false.

The electoral commission is yet to announce the final official results but the race was expected to be close between Mahama and Akufo-Addo, 76, of the centre-right New Patriotic Party (NPP), with recent polls putting the incumbent narrowly ahead.

The presidency released an unofficial tally on Tuesday claiming that results from 91 percent of polling stations showed the president with 52.25 percent of votes and Mahama with 46.44 percent.

Mahama, the leader of the centre-left National Democratic Congress (NDC), meanwhile claimed that his party had won a majority — 140 — of the 275 seats in parliament.

“We thank the Ghanaian people for the confidence they’ve expressed in us. It’s clear, the Ghanaian people want change in this country,” Mahama said.

The government strongly rejected the opposition’s claim that it had won a parliamentary majority, saying the announcement “could endanger the peace of this country.”

Oppong Nkrumah said “this dog whistle to supporters by the candidate to jubilate, to get out on the streets” was “categorically irresponsible and it flies in the face of good conduct.”

Meanwhile, the electoral commission has urged the public to wait, saying it was “working round the clock to ensure that the collated results are accurate and a true refection of the will of the people”.