The apex court directed the CBI to file a status report of its investigation before it on October 17, the next date of hearing.
CBI sources said a team will soon leave for Siwan after a case is registered by it in the murder of Ranjan.
The furore over the release of the RJD strongman from Siwan has now reached the apex court through various petitions.
The Supreme Court on Friday agreed to hear on Monday a plea seeking cancellation of bail granted to convicted gangster-turned-RJD leader Mohammad Shahabuddin by Patna High Court in a case pertaining to the killing of a youth in Siwan town of Bihar.
On the road rage incident in Gaya, Kumar said, "... when I saw in the media the (journalist's) family's demand for a CBI probe, I personally asked the DGP (director general of police) to send a police team to acquaint the family with probe (being conducted by the state police).
The apex court ordered that either the gangster-turned-politician should surrender or Bihar Police should take him in custody "forthwith".
The apex court also rebuked Nitish Kumar-led Bihar government for its lax approach in opposing bail granted to the RJD strongman.
Witnesses in the cases that controversial Rashtriya Janata Dal leader Shahabuddin has been facing have been "bumped off", the Supreme Court said on Monday, rejecting his claim of facing "media trial" in a murder case and his vehement plea for more time to prepare for his defence.
