The gunmen opened fire about 4 p.m. on two buses carrying the workers home to two predominantly Shiite areas in Baghdad , Al Shula and Sadr City .
Baghdad /location/location/contains Sadr City
DT NNS VBD NN IN CD NN IN CD NNS VBG DT NNS NN TO CD RB JJ NNS IN NNP , NNP NNP CC NNP NNP .
Baghdad
LOCATION
Sadr City
LOCATION
/location/location/contains