Several incriminating documents and cash amounting to over 5.5 million rupees (11,000 U. S. dollars) were recovered from the house of one of five left-wing Naxal rebels arrested earlier in a joint operation by city police and forces from Andhra Pradesh, central India, an official said Saturday.

The Special Task Force (STF) seized several incriminating Maoist documents, 5.5 million rupees in cash, a computer pen drive and a German-make gun from a house in Howrah's Bally municipality area, belonging to Sukumar Mandal, who was arrested along with four others Feb. 29, said a STF source.

The search and seizure operation continued till late Friday night.

Mandal, along with Rama Krishna alias RK, a mechanical engineer and chief of the Communist Party of India (Maoist)'s central technical committee, (also said to be the successor to slain rebel leader Kishenji) and three others, was remanded to Kolkata police custody till March 13.

The Kolkata police STF along with Greyhounds, an elite commando force of Andhra Pradesh, nabbed the extremists from various parts of the city.

An arms building workshop was busted and blueprints along with several key components for building a rocket launcher, explosives, Rs.2.5 lakh in cash and several rounds of live ammunition were seized in the process.

While RK and Deepak were arrested from a north locality of the city Wednesday morning, Mudi, Patra and Mandal were nabbed by the police from North 24 Parganas' Belghoria, late in the night following leads yielded by interrogation of the duo arrested earlier.

RK, who supervised Maoist operations in Andhra Pradesh, Orissa and Chhattisgarh, took over the reins in West Bengal after Kishenji alias Koteshwar Rao was killed Nov 14 by security forces in a gun battle.