Two opposition leaders have been arrested for "inciting rebellion" in Togo following Sunday's election.
Eyadema had said he would step down
Partial results put Africa's longest-serving leader, President Gnassingbe Eyadema, ahead with 59% of the votes counted so far.
But the opposition Party of Forces for Change alleges vote-rigging and some activists set up barricades and burnt tyres overnight in the Lome suburb of Be.
The BBC's Ebow Godwin in Lome says Be is cordoned off by heavily armed riot police to stop opposition activists demonstrating in the city centre.
PFC secretary general Jean-Pierre Fabre and vice-president Patrick Lawson were arrested on Tuesday morning and reportedly taken to police headquarters.
The head of the PFC, Gilchrist Olympio, was barred from the poll because he is living in exile.
But the party instead presented Emmanuel Bob Akitani, who has some 35% of the vote.
President Eyadema in power since 1967
Constitution changed so he could run again
Opposition leader barred from poll
EU aid frozen
Last year, parliament changed the constitution to let Mr Eyadema run again.
He has been in power since 1967, when he staged a military coup.
Residents of the capital said they feared trouble and although borders are officially closed, hundreds of men said their families had fled for shelter to neighbouring Ghana or Benin.
For many, memories of violence after the last elections in 1998 which left hundreds dead, are still fresh.