Gaya senior superintendent of police Garima Malik confirmed to media the arrest. "He has been arrested, we will let you know more details soon."
The 30-year-old was absconding after the incident, was arrested from Bodh Gaya, about 15 km from Gaya.
Yadav is the son of legislative council member Manorma Devi of the ruling Janata Dal (United) (JD-U).
Yadav allegedly shot dead Aditya Sachdeva, a teenager on Saturday night for overtaking his car on the Bodh Gaya-Gaya road.