GOWANDA, N.Y. (AP) – A family hike in western New York turned tragic Sunday after police say a mother and father died after falling off a cliff and their 4-year-old son was seriously injured.

Authorities say the bodies of 35-year-old Amanda Green and 33-year-old William Green, both of Buffalo, were discovered along with their son in Zoar Valley shortly before 1 p.m. Sunday. Rescuers found the couple’s 7-year-old son walking nearby.

According to Erie County Sheriff’s spokesman Scott Zylka, the 4-year-old boy was airlifted to a Buffalo hospital, where he is listed in critical condition. The 7-year-old boy is being evaluated at the hospital.

Authorities believe the two adults and child fell about 200 feet down a steep cliff but are not sure what caused the fall. Police continue to investigate.