Ten Naxalites, including two top leaders, were killed while six others managed to escape in a fierce encounter with the police in Nizamabad district this morning.This is the first major encounter in which the CPI (Maoist) suffered a large number of casualties after the Congress returned to power in May last year.Those who were killed in the encounter that took place in Manala Tanda forest area under Kammarpalli police station limits included CPI (Maoist) district committee secretary Ramesh and his wife Sunitha, and district committee member K. Babanna.Chief Minister Y.S. Rajasekhara Reddy described the shootout as unfortunate but made it clear that the government would not tolerate if the Naxalites continued to move with arms. He maintained that the second round of peace talks would take place. ‘‘We will hold talks with the Naxalites,’’ he said.Meanwhile, in another unrelated incident, Naxalites shot dead a constable in Sileru in Visakhapatnam district while he was on his way to the police station this morning.In another incident, Naxalites damaged the signalling system and set fire to the ticket counters at Annavaram Railway Station in East Godavari district, disrupting the movement of several trains between Vijayawada and Visakhapatnam.Speaking to reporters here on the encounter in Nizamabad, Director General of Police Swaranjit Sen said that a police party opened fire in self-defence when the Naxalites started shooting at them at Manala Tanda at 7.15 am.When the firing stopped after an hour, the police searched the area and found bodies of the 10 Naxalites. One AK-47 rifle, four .303 rifles, three SLRs, two SBBL guns and eight kit bags were recovered from the scene.Sen said Ramesh was involved in many offences. The shootout was a severe blow to the extremist outfit in its stronghold in Telangana districts of Nizamabad and Karimnagar, police said.