BOSTON -- A woman accidentally struck her 3-year-old son and her nephew while they were playing with chalk in her driveway Saturday, police said.

The two toddlers were hit at about 11:55 a.m. when the woman arrived at her home on Hawthorne Lane in a 2004 Toyota Sequoia. Police said the driveway slopes downward and the woman didn’t see the boys playing below.

The woman’s son and her 5-year-old nephew were transported to a local hospital for treatment. Both boys were conscious after the accident, but the extent of their injuries is unknown.

The incident is being investigated by an accident reconstruction specialist from the Norwell Police Department.