Photo of Karachi bomber released

By Kamran Haider

KARACHI (Reuters) - Pakistani police released a photograph on Saturday of a suicide bomber who killed at least 139 people, as opposition leader Benazir Bhutto worked out her next step after the bloody start to her comeback campaign.

The militant threat demonstrated to such devastating effect in Karachi on Friday raised fears over the prospects for a national election due in early January that is supposed to mark a transition from military-led to civilian-led democracy.

Prime Minister Shaukat Aziz told reporters in Lahore the election schedule would not be affected, and caretaker governments would be in place at federal and provincial levels after November 15.

Interior Minister Aftab Ahmed Khan Sherpao, however, voiced concern that campaigning could be restricted due to security worries. Both Aziz and Sherpao have survived suicide attacks.

Urdu language newspapers carried passport-sized photographs of the head of the suicide bomber propped on a white sheet.

The dead eyes stared blankly out of the chubby, unshaven face, the heavy growth apparent around the jawline and top lip. The man appeared to be in his twenties.

"The age of suspect is in between 20 to 25 and he looks to be a Karachiite," a security official, who requested not to be identified, told Reuters.

A police statement said at least 139 people died in Friday's attack and 325 were wounded.