New Delhi, Oct 18: Congress Vice President Rahul Gandhi on Wednesday condemned the killing of an RSS leader in Ludhiana, saying "violence is unacceptable" and demanded that the guilty must be brought to book. "I strongly condemn the killing of RSS leader Ravinder Gosai in Ludhiana. Violence is unacceptable. The guilty must be brought to book," Gandhi said in a tweet. Gosai was shot dead by two unidentified motorcycle-borne assailants on Tuesday when he was returning from a Rashtriya Swayamsewak Sangh (RSS) shakha (daily training in the early morning). He was the Sangh Pracharak (regional missionary) at the RSS shakha in Ludhiana. On Tuesday, Union Home Minister Rajnath Singh raised the issue with Punjab Chief Minister Amarinder Singh, who said the police was working on some leads and would nab the culprits soon. The killing was condemned by BJP and RSS leaders in Punjab on Tuesday, who said the law and order situation in Punjab had deteriorated under the present Congress government.