Maoists are regrouping in West Bengal's Jangalmahal area, where peace prevailed for more than a year after their leader Kishenji was killed and several other top functionaries were arrested, according to the State Intelligence Bureau.

Jangalmahal, which comprises three districts of West Midnapore, Bankura and Purulia, where killings and encounters between Maoists and security forces were almost the order of the day since 2008, saw relative peace since the middle of 2011.

But the latest intelligence reports said the ultras in small groups were trying to regroup in the area and rebuilding their movement from a scratch.

"We have specific inputs that Maoists are trying to regroup in the region. The squads of Maoist leaders Bikash in the Lalgarh area (W Midnapore), Ranjit in Ayodhya hills (Purulia), Madan Mahato in Jambani, Akash and Jayanto are trying to regroup and recruit new people," SIB ADG, Banibrata Basu, said.

One reason why the Maoists are keen to come back to the area is the topography of the area which with its deep forets and hilly terrains provide an ideal backdrop for their clandestine activity.

Another factor in their favour is the ready source of cadres among the long-exploited tribal people in the entire region which is underdeveloped in terms of job availability and infrastructure.

The terrain also suits their methods of guerrilla warfare while taking on the security forces and police personnel.

The area, which recorded 350 killings in 2010-11, witnessed none in 2012.

According to sources, Maoist commanders Bikashs wife Tara, Madans wife Jaba and Jayanto are engaged in reviving the movement and rebuilding the support base among the tribals.

IG western range Gangeshwar Singh said the security forces were well prepared to combat any revival of Maoists insurgency in the area.

"Bikash, Akash, Madan, Ranjit are moving with small squads in Junglemahal area. They are trying to regroup and establish contact with the people of the area," Singh told PTI.

Reacting to the development, Maoist ideologue Vervara Rao said, "It is the natural process of an armed movement.

Once you are back and once you strike back regrouping and retreating are part of any guerrilla movement. If the promised development doesnt take place in Jangalmahal, people of the area will again rise in revolt."

Since the nineties, the Maoist movement in Bengal, which is the ideological offspring of Naxalbari revolution of the 60s and early 70s, had a thin base in Jangalmahal and had ideological presence only among a section of students and intellectuals of Kolkata.

It started gaining momentum in 2007 during the anti-land acquisition protest in Nandigram which ultimately saw the Left Front regime being ousted in the 2011 Assembly election.

The deadly attack on former chief minister Buddhadeb Bhattacharyas convoy at Salboni in West Midnapore district, near Lalgarh, in November, 2008 by the Maoists gave rise to a spontaneous tribal movement known as the Lalgarh movement.

The movement swiftly spread its wings in the adjoining districts of Purulia and Bankura under the banner of the Peoples Committee against Police Atrocities (PCAPA), a Maoist-backed organisation led by Chattradhar Mahato, who is currently in prison.

But the reins of the movement quickly changed hands and by the beginning of 2009, the Maoists, who always cashed in on the anger of the masses against state oppression and underdevelopment, hijacked the entire movement.

Maoists with their guerilla tactics and increasing mass base quickly transformed several parts of Jangalmahal into free zones'', followed by rampant killing of CPI(M) cadres and security personnel in the area.