Two of the injured were police and a 12-year-old girl was also wounded in the blast in the city of Diyarbakir, Anatolia news agency was quoted as saying.

"The attack targeted a tailor's shop in which there were police officers. A policeman was killed and five people injured," Diyarbakir governor Huseyin Avni Mutlu was quoted as saying by Anatolia.

Earlier, officials and witnesses had said the bomb targeted a police vehicle and also damaged a shop. Some witnesses said the device used in the attack was a hand grenade.

It was not immediately known who was behind the attack.

The separatist Kurdistan Workers' Party (PKK) is active in the region and has routinely targeted the security forces. The PKK is considered a terrorist group by Turkey and much of the international community.

Prime Minister Recep Tayyip Erdogan's announced on Wednesday that the government was drafting a motion asking parliament to authorise a cross-border military operation into northern Iraq to crack down on PKK militants who take refuge there.

The government decided Tuesday to step up measures against the rebels, "including a cross-border operation if necessary," following an upsurge in PKK violence.

Fifteen soldiers were killed in rebel attacks at the weekend, triggering a public uproar and increasing pressure on the government to take tougher action.

The PKK has fought for Kurdish self-rule in the southeast since 1984. The conflict has claimed more than 37,000 lives.