Maoists operating in south and central parts of the state suffered a setback when four of its activists were arrested and a huge cache of arms was seized during an operation in Rohtas and Kaimur districts on Monday.

Acting on a tip-off that the rebels owing allegiance to the Ajay Rajbhar faction had assembled on the Kaimur plateau to carry out a major operation, a joint team of the Rohtas police and Central Reserve Police Force launched a search operation.

During the operation, the security personnel recovered 17 weapons, 80 live cartridges and nabbed four associates of Rajbar, a self-proclaimed area commander of the rebel outfit. The police also found a huge quantity of explosives from Badhua village.

Rohtas superintendent of police Chandan Kumar Kushwaha said the security forces recovered two 3.15 bore rifles, 13 single-barrel guns, a pistol, 80 cartridges of .315 bore and 12 bore, two sacks of gunpowder and 55 batteries used in making improvised explosive devices (IEDs) on the basis of grilling of those arrested.

Kushwaha said the arrests were made during two-day operations against the rebels, particularly Nauhafta forests, considered to be hotbed of the rebels. 'The police came under fire during the combing operations near Banda hill area of the district. The police returned the fire and forced them to surrender,' he said.

While the Maoists fired over 50 rounds, the police could return only 10 in the incident. Three of the four arrested rebels were later identified as Jokhan Singh, Singasan Yadav and Amalu. While Jokhan and Amalu were residents of Rohtas, Singasan belonged to Kaimur district.

A medical practitioner, identified as Dr Amanullah, was also nabbed for his alleged links with the rebels. Additional superintendent of police (operations) Sohail Ahmed revealed that the Maoists had changed their modus operandi to hoodwink the security forces.

'Maoists nowadays don't carry weapons with them for any operation. Instead, the activists are provided weapons from the nearest storeroom, where both sophisticated and regular weapons are stored for the purpose. This helps them to conceal their identities while switching locations,' said Sohail.

Earlier, the rebels used to carry their weapons with them, running the risk of being intercepted and seizure of their firearms. 'The arrest of four rebels gave a jolt to the Ajay Rajbhar group, which was active in bordering areas of Rohtas and Kaimur, Palamu and Garhwa in Jharkhand and Sonebhadra in Uttar Pradesh,' said Sohail, adding that efforts were on to arrest the self-styled area commander.

Sources said Rohtas resident Ajay Rajbhar had surrendered before the UP police in August 2012. Later, he was released from jail on bail. 'After coming out of jail, he again reorganised his associates and started collecting levy,' said a police officer associated with anti-Naxalite operations.