The newly-elected MLA along with his supporters was returning home after paying obeisance at a temple in his constituency after his electoral win, the police said.
Around four rounds were fired at the convoy of the party's MLA from Mehrauli.
Police says 'case of personal enmity, Naresh Yadav wasn't targeted'
Delhi Police on Wednesday arrested one suspect in the incident and asserted that Yadav was not the target of the attack but the assailant specifically attacked the AAP worker, who was shot dead in the incident.
"The investigation so far reveals that there was one assailant. Naresh Yadav wasn't the target. The assailant had specifically come to target the man who was shot dead (AAP volunteer)," said Southwest Additional DCP Ingit Pratap Singh.
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In a tweet, Aam Aadmi Party (AAP) leader Sanjay Singh on Tuesday night claimed party volunteer Ashok Mann was killed in the attack.
"Convoy of MLA Naresh Yadav attacked in Mehrauli, Ashok Mann killed. Naresh Yadav was returning home after visiting a temple," Singh said in a tweet in Hindi.
"Shots fired at AAP MLA @MLA_NareshYada and the volunteers accompanying him while they were on way back from temple. At least one volunteer has passed away due to bullet wounds. Another is injured," the AAP said in a tweet.
Ankit Lal, AAP's social media in-charge tweeted: "Multiple shots were fired at AAP MLA @MLA_NareshYadav & @AamAadmiParty volunteers accompanying him to his home in Mehrauli after visiting a temple as part of victory procession. Miscreants in another car opened fire near Fortis. 1 dead and 1 injured. Police is at the spot."
The AAP swept the Delhi Assembly elections as it bagged 62 of 70 seats here.
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