NEW : Six of at least 27 people killed are civilians , police say . NEW : The building located in western Baghdad had an ice cream parlor and medical center . A bomb was hidden in a plastic bag and detonated around 3 pm local time . There have been several protests ahead of Saturday 's provincial elections .
NEW : Four of at least 27 people killed are children , police say . NEW : The building targeted in western Baghdad had an ice cream shop and medical offices . A bomb was hidden in a plastic bag and detonated around 10 p.m. local time . There have been several attacks ahead of Saturday 's provincial elections .