Liberia's Ellen Johnson-Sirleaf has a narrow vote lead over her main presidential rival Winston Tubman, according to a tally by a local independent media group of ballot slips counted so far on Wednesday.

Johnson-Sirleaf collected just over 96,000 of 220,000 votes counted so far, with Tubman at just under 80,000, the Liberia Media Center said. The tally was based on its reporters calling in results pinned up at polling stations across the country.

Around 1.8 million Liberians registered to vote in Sunday's election, the second since its 1989-2003 civil war. If no candidate wins an outright majority, the two front-runners will go into a run-off vote scheduled for November 11.