At least four people were killed and 52 injured yesterday when a bomb destroyed a military vehicle in a southeastern Turkish city, Prime Minister Tayyip Erdogan said.

The Anatolian state news agency later put the death toll at five and said it included two school students.

Diyarbakir is the biggest city of mainly Kurdish southeast Turkey and home to large numbers of troops who are battling PKK Kurdish rebels both inside Turkey and in nearby northern Iraq. The blast will keep up pressure on Turkey to strike PKK positions in northern Iraq.

"We will continue our fight against terrorism with the same determination, whether domestically or internationally," Mr Erdogan told reporters. He said six people had been seriously injured. Diyarbakir's governor said the total number of those hurt in the blast was 68. He said the bomb had been set off by remote control.

Turkish television showed vehicles engulfed in flames as ambulances and firefighters rushed to the scene. One man's face was covered with blood.

"The place where the explosion happened was full of people, there was a private school right in front of it," a police officer told Reuters.

A large hotel and shopping centre are near the site of the blast, as well as large military installations.

Several explosions happened one after another, witnesses said, but it was not clear whether the later blasts were caused by exploding fuel tanks or another bomb.

Turkish security forces have been on alert over the New Year for possible attacks by the Kurdistan Workers Party (PKK) and its supporters.