Police in Nanporo, Hokkaido, have arrested a 17-year-old girl on suspicion of stabbing to death her 47-year-old mother and her 71-year-old grandmother at their home.

According to police, the two bodies were found by the suspect's 23-year-old sister when she returned home at around 2:30 a.m. Wednesday, TBS reported. The women's bodies were found in separate rooms, police said, adding each body had several stab wounds.

Police said the girl has admitted to killing her mother and grandmother while they slept, and that afterwards, she took her older sister's car and drove to a park about 4 1/2 kilometers away, where she threw the knife.

Police quoted the girl as saying she was sick of being disciplined by her mother and grandmother and just had to break free.

© Japan Today