The elderly woman was walking home from the grocery store in the 3100 block of 51st Street East just before noon Aug. 5 when she was approached by the suspects.
The victim told officers the women threatened to shoot her if she did not give them her purse. They grabbed her purse and fled in a vehicle, police said.
Last week, investigators released photos of the two suspects and asked for the public's help in identifying them, and "within minutes" of the photos being publicized by area media outlets, police say they had dozens of tips from people who knew the women by name.
Both of them were arrested within the past few days.
Minneapolis police thanked people for helping them find the suspects.
"This is a fantastic example of the truly positive outcome possible when the public is willing to provide information," said police. "This case was solved by the members of the public who cared more about a 90 year old victim than anything else."
One suspect, 30-year-old Morgan Elizabeth Bierman, has been charged. The other suspect is expected to be charged Tuesday, according to Minneapolis police.