Deadly blasts hit Pakistani city of Karachi 22 November 2013 Last updated at 22:02 At least seven people are reported to have been killed in two bomb explosions in a busy area of Pakistan's southern city of Karachi. At least 18 people were injured in the predominantly Shia area of Ancholi, local media report. Angry crowds gathered at the scene, denouncing the attacks. The improvised explosive devices (IEDs) were placed on motorcycles parked near cafes and tea stalls, police. Shia-Sunni tensions Local police official Javed Odho told AFP news agency that the IEDS had gone off "with a big bang." He said it was difficult to say immediately whether Shia were the target because Sunnis also lived in the vicinity of the blasts. Women and children were reported to be among those injured. The blasts damaged shops and power transmitters, causing a complete blackout in the area. The power was later restored. Security forces have now been put on high alert across the city. Sindh province Information Minister Sharjeel Memon condemned the attacks, describing them as a cowardly act. Shia groups have also denounced them. A day of mourning has been announced for Saturday. Tensions remain high in Pakistan following recent sectarian violence between Sunni and Shia Muslims that led the government to impose curfews and block mobile phone networks. Earlier on Friday, Sunni parties observed a largely peaceful day of protest against last week's sectarian clashes in the garrison city of Rawalpindi. The violence erupted in the city, near the capital Islamabad, as Shia Muslims staged a procession marking the religious festival of Ashura. Eight people died and dozens were injured.