Indian Maoists killed at least 11 paramilitary troops and left 50 wounded in one of the major encounters in Jharkhand on May 3. In Orissa, one trooper was killed and four others were injured on May 2. Three policemen were wounded in a landmine blast in Bihar on the same day. Media reports about the incidents of barely a couple of days said the Maoists have taken advantage of the weakening of the central government-sponsored Operation Green Hunt. About 250 , 000 paramilitary forces and police have been deployed in the anti- Maoist operation about three years ago with the target of eliminating the red rebels within 2 years' time. But the Maoist movement, purportedly aimed at securing the rights of the deprived, oppressed tribals and dalits whose average income is Rs 20 a day, has now extended up to Punjab posing the gravest internal security threat to India. Police accounts said about 400 Maoists, including men and women, on Tuesday carried out the ambush in a forested area of Jharkhand that killed 11 security personnel and injured as many as 50 - the biggest such attack in the state in two years. Some 100 paramilitary forces and police on secret information launched operation against the Maoists. Finding none of them, the group was returning to the camp and caught in the blast of one of the landmines planted in two kilometres stretch. Through hailers the Maoists asked the forces to lay down arms and surrender. They refused to surrender. The fierce gunfight left eight paratroopers and three police killed and 50 others wounded. Most of them were airlifted to state capital Ranchi, seven of them in a critical condition. "If there had been delay in backup support, then the casualty could have been much more," said a police official. In another encounter, police claimed busting of a transit camp of the Maoists at Jhumara hillocks in the state on Tuesday. CRPF assistant commandant JP Yadav was wounded by bullet in the encounter. He was evacuated by helicopter. Yet another encounter took place in Ranchi district early Tuesday morning when deputy police super Anand Joseph Tigga was badly wounded by bullet. In Orissa, a paramilitary jawan was killed and five others were injured in an encounter with the Maoists in a forest area last Monday. A group of 21 paramilitary troopers on patrol in Khandamal district came under sudden attack by the Maoists. The area is known as communally sensitive. A Hindu leader and his four aides were killed by Maoists three years ago triggering widespread communal violence lasting for several months. At least 38 people were killed in the violence. Maoists in the state have warned of taking revenge for violation of agreement by the government reached with them last month for securing release of a district collector and junior engineer abducted by them. The government had accepted all the 14 demands including halting of Operation Green Hunt, release of some 600 tribals arrested for suspected involvement in Maoist movement and compensation to the families of innocent tribals killed in anti-Maoist operation. Soon the state government, ostensibly at the behest of the centre, resumed Operation Green Hunt and refused to implement any of the demands. In Bihar, three policemen were injured when Maoist blasted a landmine in forest area of Muzaffarpur district last Monday. A report from Punjab said 15 people including seven police personnel were arrested for involvement in supply of firearms to the Maoists. Police said inter- state gangs are engaged in trading guns which are procured from clandestine factories in Bihar, Uttar Pradesh and Madhya Pradesh. This has worried the government. The State Congress president Amarinder Singh asked the police for greater vigil against Maoist activities. The red rebels started spreading network in Punjab and sale of weapons to them is an ominous indication, said Singh and called for taking care of the youths, particularly those who are educated but unemployed as they can easily fall prey to any sinister design. Maoists in trouble-torn West Midnapure of West Bengal are lying low these days because of heavy mobilization of central security forces for on-going state assembly elections. "They are very active and only waiting for the withdrawal of central forces after the polls," said police super MK Verma. Three central leaders of CPI ( Maoist) were arrested in Bihar this week. One of them, Varanasi Subramanyam, is believed carrying out the responsibility of Kobad Gandhi arrested two years ago. The government announced Rs. 2 lakh reward for the security men who arrested the Maoist leaders. They were lodged in high security prison at Katihar.