Police on Saturday said that 28-year-old Adesh Ganjhu alias Mangra, a member of the banned Tritiya Sammelan Prastuti Committee, was arrested in Jharkhand's Latehar district in an anti-Maoist operation. "A huge cache of arms and ammunition was recovered during the operation. This is for the first time that ultra-modern 40 mm HE grenades have been seized," Latehar SP said.