An 18-year-old man transporting the bomb for an alleged attack on behalf of the rebel Kurdistan Workers' Party (PKK) lost his hands in the explosion, the source said.

His 16-year-old presumed accomplice was also wounded in the blast along with two 14-year-old passers by who were hit by shrapnel.

Abdullah Ocalan, the PKK's imprisoned leader, declared a historic ceasefire in March after months of clandestine negotiations with the Turkish secret service.

However the peace process was rattled by the death of a young Kurdish man during an anti-government protest in the southeast last month.

The PKK first took up arms for Kurdish self-rule in southeastern Turkey in 1984, sparking a conflict that has cost some 45,000 lives.