A Pennsylvania teenager has been arrested on homicide charges after she, her boyfriend and her friends killed her 71-year-old grandfather.

Gabriella Long, 17, was charged along with her boyfriend, Chris Cortez, 19, and friends Mercedes Hall, 16, and Devin Cunningham, 20. Police say they stabbed Joseph Monka to death in his Edwardsville home, where Long also lived. 

"We have very young defendants charged with killing an elderly member of this community," Luzerne County Assistant District Attorney Jarrett Ferentino told WNEP, an ABC affiliate in Scranton.

The group allegedly killed Monka on Monday, according to court papers.

Cortez reportedly admitted to authorities that he stabbed him in the neck, adding that Cunningham beat him with a golf club. The four individuals then stole Monka's car, making off with $30,000 in cash that he had in a safe.

The teens were found with the stolen car at a hotel in the nearby city of Wilkes-Barre. Cunningham was not amongst the group and police are still searching for him.

Monka's body was not found until Wednesday, after family and friends grew concerned when they did not hear from him. Neighbors say they did not know him well but recalled seeing his granddaughter come and go regularly.