LOME (Reuters) - Youths set up blazing barricades and fired rocks at riot police in an opposition stronghold of Togo's capital on Friday after police broke up a march to demand a delay to presidential elections this month.

Protesters burned tires and rubbish on streets in the Be suburb of the capital Lome and used large stones to block roads. Police repeatedly fired tear gas and broke down the barricades, but the youths returned to set up more.

Friday's running battles came after some 2,000 protesters wearing T-shirts and scarves in the yellow color of the main opposition party, tried to march on the town hall to demand their voting cards for the April 24 polls.

Paramilitary police armed with batons and riot shields fired tear gas and chased fleeing youths and women, but they regrouped in Be, where protests have regularly turned violent in the past.

Togo slipped into chaos in February when Gnassingbe Eyadema, who ruled the former French colony for 38 years, died.

The army named his son, Faure Gnassingbe, as leader, violating the constitution and sparking deadly street protests. Under intense international pressure, Gnassingbe agreed to step down at the end of February and run for office in the election.

A coalition of six opposition parties has demanded the poll be delayed, accusing the authorities of "serious irregularities" in compiling voter lists and saying there has not been enough time to organize the vote, called to resolve the crisis.

On Wednesday, police also broke up a demonstration and opposition parties said a 3-year-old child was suffocated by tear gas and 21 others were seriously injured.

There was no official confirmation of casualties. A human rights group said 19 people at a ruling party rally, also on Wednesday, were injured during attacks by opposition supporters.

CALLS FOR CALM

Friday's protest coincided with the start of official campaigning for the presidential election.

Togo's interim President Abass Bonfoh on Thursday called on all candidates to promote national unity in a country that had already suffered from political violence.

"I exhort you all to avoid during this electoral period the splits and excesses that could transform these polls into sterile confrontations, expressions of rancor and a settling of accounts," he said in a speech broadcast on state radio.

There are four candidates: Gnassingbe, opposition candidate Emmanuel Akitani-Bob, head of a small opposition party Harry Olympio, and businessman Nicolas Lawson who heads the PRR party.

On Thursday, the Interior Ministry said 41 percent of voter cards had been handed out in Lome and 64 percent of voters across the former French colony now had their cards.

"We need to restart the revision process which has been characterized by a desire to favor one camp and stop the other from taking part in a democratic manner," said Jean-Pierre Fabre, secretary general of Union of Forces for Change party.

Ministry figures showed that 55 percent to 60 percent of cards had been distributed in the center and north of the country, areas that traditionally favor Gnassingbe's ruling RPT party.

Interior Minister Francois Boko said "some deficiencies" had been noted in the process to register voters.

He said eligible voters in the capital would have another chance to get their cards at two football stadiums at the weekend, even though officially the process ended this week.