Khunti: An elderly tribal couple was killed by unidentified persons for allegedly practising witchcraft at Kudlum in Khunti district, police said Tuesday. Jaswa Heren (60) and his wife Basanti (55) were found dead with cut wounds sustained by sharp weapons on their bodies near Bigadon railway gate yesterday, Superintendent of Police Anish Gupta said. Police suspected that the couple was killed by local villagers for practising black magic, he said.