Police said the 21-year-old woman was on her way back to a home for asylum-seekers in the town of Bad Belzig, about 100 kilometers (60 miles) southwest of Berlin, on Wednesday afternoon when she was attacked by two boys, aged 14 and 15, and a 14-year-old girl, the dpa news agency reported.
They are alleged to have pulled away the sack of potatoes she was carrying on her head, thrown her to the ground and assaulted her.
Bild newspaper reported today the woman had to be treated in a hospital for her injuries, but no other information on her condition was immediately available.