The Supreme Court on Friday expressed concern over alleged politician-criminal nexus in Bihar and sought response from Nitish Kumar government in the Siwan journalist Rajdeo Ranjan murder case.

The apex court was hearing a plea of slain scribe's wife's to transfer the case to Delhi, citing the fact that she will not get a fair trial in Bihar.

She contended that free and fair trial was not possible in Siwan and pleaded the SC to monitor the probe which has been handed over to the CBI.