(CNN) A 97-year-old woman apparently slipped and fell while walking to her car. Her twin sister, running into the house to call for help, tripped on a rug.

Both were found dead the next morning, and police believe they may have frozen to death.

The tragic deaths took place over the weekend in Barrington, Rhode Island.

Martha Williams was walking to her car after having dinner with her sister Jean Haley on Friday.

"Ms. Williams may have fallen in the driveway," Police Chief John LaCoss said in a statement. "Ms. Haley may have tripped on a rug on the floor of the garage as she attempted to enter her house to call for assistance."

The precise cause of death hasn't been issued but extremely cold temperatures might have been a factor in the deaths, La Coss said.

CNN's Joe Sutton contributed to this report.