A man and a woman were detained on Wednesday while they were protesting outside the Parliament building carrying cans that emitted a yellowish and red smoke, the police said in New Delhi.
The incident happened minutes after two people jumped into the Lok Sabha chamber from the public gallery and opened canisters that emitted a similar-coloured smoke, triggering panic among the MPs.
The Delhi police's special cell will investigate both the incidents, according to officials.
They said the two detained outside Parliament were identified as Neelam (42), of Haryana's Hisar, and Amol Shinde (25), of Maharasthra's Latur area.
After opening the gas canisters that emitted the smoke outside the Parliament building, the two protestors raised slogans such as "Tanashahi nahi chalegi" (dictatorship will not be allowed), "Bharat Mata Ki Jai" and "Jai Bhim, Jai Bharat", the officials said.
The incidents came on a day when the nation is observing the anniversary of the 2001 Parliament attack. Terrorists of the Pakistan-based Lashkar-e-Tayiba and Jaish-e-Mohammed outfits attacked the Parliament complex on this day in 2001, killing nine people.
Narrating Wednesday's episode, Congress leader in the Lok Sabha Adhir Ranjan Chowdhury said, "One person was seen leaping over the benches of the Lok Sabha while another was seen dangling from the public gallery, spraying some tear gas when Zero Hour was in progress."
A senior police official said one of them was identified as Sagar, who entered the House using a pass issued on an MP's recommendation.
He said the intruders were in the Parliament security unit's custody. "Both are being interrogated by security officials. They will be handed over to the local police," the officer said.
In a post on X, Congress leader Gaurav Gogoi said, "Saw two young men unleash foul smelling yellow coloured gas from canisters inside Parliament gallery. MPs rushed to grab these men. One person was raising some slogans. This raises serious questions on another aspect of the new Parliament building- security."
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