Two persons were killed during an attempt on the life of a local Shiv Sena leader who was also injured at Ambernath town on Wednesday night,police said. Four unidentified persons armed with sten-guns entered Shiv Senas office in Ambernath and opened fire at the partys local unit chief Arvind Walekar injuring him,they said. Walekars bodyguards quickly surrounded him and one of them was fatally hit by a bullet,police said. The bodyguards too fired back,killing one of the assailants,they said. Walekar has been admitted to a local hospital,police said. It is suspected that the incident was the fallout of old enmity,the police said,adding that they have launched a manhunt for the attackers. Walekar,a former president of the Ambernath Municipal Council,was named as an accused in a criminal case but was subsequently acquitted by the Sessions Court. Security has been stepped up at Ambernath,located on the outskirts of Mumbai,following the incident,police said.