With over a quarter of votes counted in the Guinea Bissau presidential run-off elections, electoral officials say partial results show the opposition leader Kumba Yallah of the Socialist Renewal Party has a strong lead.

The Reuters news agency quotes a senior electoral officer Filomeno Lobo de Pina as saying Mr Yallah polled seventy-five percent of the votes counted so far.

That is fifty percent more than his rival, the interim president Mallam Bacai Sanha of the former ruling party the PAIGC.

The elections are meant to return Guinea Bissau to democratic rule after a civil war and an army coup.

Final results are expected on Saturday.

From the newsroom of the BBC World Service