Rocky Yadav, the son of a JD(U) legislator, on Tuesday confessed to his involvement in the killing of teenager Aditya Sachdeva in Bihar's Gaya district, a police officer said hours after the accused was arrested.
"In his statement, Rocky Yadav admitted to committing the crime. I assure you that we will soon arrest others who were involved in the crime," Gaya's Senior Superintendent of Police (SSP) Garima Malik told reporters.
The police have also recovered the pistol used in the killing of Aditya Sachdeva, she said.
"The arms licence was issued in Delhi," Malik said.
The investigation continues and Rocky Yadav will now be produced in court, the SSP said.
Earlier on Tuesday, Rocky Yadav, 30, was arrested from a house in Bodh Gaya, the police said.
Rocky allegedly shot dead Aditya Sachdeva, the teenaged son of a businessman, on Saturday night for overtaking his car on the Bodh Gaya-Gaya road.
The accused is the son of legislative council member Manorma Devi of the ruling Janata Dal (United) or JD-U.
His father Bindi Yadav, a criminal-turned-politician, was with him in the car along with a bodyguard when the crime took place.
While Rocky has been absconding since the incident, his father and the bodyguard were arrested and sent on Monday in 14 days' judicial custody by a local court.
Bindi Yadav has a criminal record. He was earlier arrested after a huge cache of AK 47 cartridges was seized from him.
On Monday, the killing reverberated inside and outside parliament as the Bharatiya Janata Party (BJP) attacked Bihar Chief Minister and JD(U) President Nitish Kumar for allowing the "return of jungle raj" in the state.
The BJP had called a shutdown of Gaya town on Monday.
Nitish Kumar said his government will not spare anyone found guilty of the crime as no one is above the rule of law.