Security was tight for Erdogan's visit to Diyarbakir, the regional capital of the mainly Kurdish southeast, which the ruling Justice and Development Party (AKP) is seeking to win from the Democratic Society Party (DTP), the country's main Kurdish party, in the March 29 elections.

The AKP hopes that such a win would provide a chance to solve a decades-long armed conflict by separatist Kurdish rebels that has wreaked havoc in the impoverished region.

Police were out in full force over fears of violent demonstrations by supporters of the rebels, but there were only a few incidents of small groups burning tyres and shouting anti-AKP slogans far from where Erdogan was addressing a crowd of some 20,000 people.

A number of demonstrators were detained, a local security source said, but gave no figure.

In a speech often interrupted by applause, Erdogan pledged to bring better services to Diyarbakir and underlined government plans to pump billions of dollars into infrastructure projects in the region.

"A new era will begin on March 29.... On that day, Diyarbakir will finally have the services it deserves. Our only aim is to serve the people," Erdogan told the crowd gathered despite rain and chilly temperatures.

Erdogan has on several occasions publicly accused the DTP of failing to do a proper job of running the city and has also slammed the party for failing to condemn the Kurdistan Workers' Party (PKK) rebels fighting for self-rule in the southeast.

The DTP is currently facing a possible ban for links with PKK rebels. The party, which urges a peaceful resolution to the conflict, denies the allegations.

Erdogan also called on the Kurdish community to shun support for the PKK and work with his government to increase democracy in the region.

"Let us protect this republic together.... Everyone should know that violence and terrorism are the enemies of rights and liberties," he said.

More than 40,000 people have been killed since 1984 when the PKK, blacklisted by Turkey and much of the international community, took up arms to carve out a Kurdish state in the southeast.

The government is under pressure to back the military campaign against the rebels with social and economic measures. In recent years, it has granted the Kurds more cultural rights and last month launched a Kurdish-language television channel.