Those detained include PCAPA (Peoples Committee Against Police Atrocities) members and gangmen. One reportedly was directly involved in removing pandrole clips from the tracks on early Friday morning,leading to the derailment. Investigations are on and eight to 10 people have been brought for interrogation. However we are yet to arrest anybody, West Bengal DGP Bhupinder Singh said,after a meeting attended by top CID officers of the state. CID sources said it was just a matter of time before alleged masterminds Bapi Mahato and Umakanto Mahato were arrested. Incidentally,Umakanto was bailed out as recently as January after police failed to prove charges against him, which included those of waging a war against the state. Police believe he led the squad that planned the Jnaneswari attack. Umakanto had been arrested in June last year from near Jhargram. After his interrogation,15 live landmines reportedly planted by him in various areas were recovered. Even the man alleged to be behind the detainment of Rajdhani Express in October last year in Jhargram Banstolla Halt,Dhanapati Mahato,is now out on bail.