A man threw chilli powder at Delhi Chief Minister Arvind Kejriwal outside his office in the secretariat on Tuesday, provoking outrage from his party. The attacker, identified as Anil Kumar, has been taken into custody, officials said.
Arvind Kejriwal was leaving for lunch when the attack took place outside the chief minister's chamber on the third floor.
The man, identified as Anil Kumar, was caught after the attack.
Calling it a dangerous attack, Mr Kejriwal's Aam Aadmi Party tweeted: "Serious security lapses from Delhi Police. Even the Chief Minister is not safe in Delhi."
AAP spokesperson Raghav Chadha said he was behind the Chief Minister when the attack took place.
Mr Kejriwal, 50, has in the past been attacked with ink, slippers and slapped while campaigning for elections.
