"Now the police is inquiring into the incident. If required, a separate probe would be instituted," Munda told reporters here. Valsha John (52) was hacked to death on Tuesday by about 35 to 40 unidentified persons at her house in Pachwara under Amrapara block in Pakur district.

She hailed from Kerala's Kudapali village in Ernakulam district and came to Pakur 12 years ago. Around three years ago, she began her protest against mining by Panem Coal Company. According to locals, the stir began after villagers feared displacement following mining.

DIG (Santhal Pargana) V K Pandey had yesterday said that police suspect reports of Valsha's withdrawal from the anti-displacement movement against the company might have been the reason behind the incident.

Pakur SP Amarnath Khanna said after Valsha returned on November 7 from her village in Kerala, some villagers had protested her return. However, no arrests were made in this connection.

Former Jharkhand deputy chief minister Stephen Marandi said the mortal remains of the nun was today laid to rest in Dumka district. "The nun was buried at Dudhiyani in Dumka this morning," said Congress leader Marandi, who had won five times from Dumka Assembly constituency.

"She used to represent a local committee during talks with the management of the Panem Coal Company on various demands and other matters (pertaining to displacement), besides running a school and a hospital," he added.

On October 12, 2009, the company's deputy director Dinanath Sharan was also gunned down by suspected Maoists in Pakur while he was on a morning walk. Meanwhile, Jharkhand Disom Party today demanded a CBI probe into her killing.