The death toll in a bomb attack on a busy commercial street in northeastern Baghdad has climbed to at least 30, with scores wounded, police and hospital sources said Friday.

Two explosions struck the Shi'ite neighbourhood of Ur near the capital's teeming Sadr City slum Thursday evening, highlighting Iraq's tenuous security situation as U.S. troops prepare to withdraw by December 31.

Thirty people were killed in last night's explosions including five security personnel, and 100 people were wounded, including four security personnel, an Interior Ministry source said on condition of anonymity because he was not authorised to speak to the media.

Hospital sources and another Interior Ministry source put the toll at 31 dead and 71 wounded. Police said Thursday at least 18 people had been killed.

Security forces have been targeted in numerous attacks in recent days as militants try to undermine Iraq's fragile coalition government while the remaining 39,000 American troops pull out, more than eight years after the 2003 invasion that ousted Saddam Hussein.

Violence has tumbled in recent years following the sectarian slaughter of 2006-07, but Iraqi security forces are still fighting a lethal Sunni insurgency and Shi'ite militias that carry out hundreds of bombings and other attacks each month.

(Reporting by Waleed Ibrahim; Writing by Muhanad Mohammed)