Nine-year-old climate activist Licypriya Kangujam on Sunday said she was detained by the Delhi Police for protesting outside Parliament House against the rising air pollution levels in the Capital. Aarav Seth, a 12-year-old boy, who was demonstrating with Kangujam was also detained, she said.

In a series of tweets from her account that is managed by her guardians, Kangujam said she and Seth were detained from the protest site for over 40 minutes. She said the police had also called in Central Industrial Security Force personnel to take them.

The activist said they were escorted in a police vehicle to an unspecified location. “They took her somewhere but we couldn’t trace her,” said a tweet by her handle, along with a picture of the police vehicle that reportedly took her.

They were later found near Jantar Mantar. Seth, the 12-year-old boy, who was detained with Kangujam said the police had initially tried taking them to the Parliament Street Police Station.

Kangujam said that after her release, the police gave her a last warning and told her that she would be arrested the next time if she held demonstrations there.

“My only mistake was I protested in the most highly restricted security zone of India,” she added. “Anyway, they released me without any conditions after some time in Jantar Mantar. But usually I protest every week there as a routine campaign to give awareness to the people on climate change.”

Kangujam said her detention was illegal. “Under what law, how a nine years old kid can be arrested or detained? It is illegal detention,” she tweeted. The nine-year-old said she would continue to hold protests. “This is my right to raise the voice to give us clean air to breathe,” she added. “If I don’t tell to our leaders then to whom I should tell? My demand is for them too.”

The air quality of Delhi-NCR typically deteriorates in the winter. It was in the “poor category” for six consecutive days after it began to decline on October 7 for the first time in over three months.

In November last year, the court had passed a slew of directions to check air pollution. The court had asked Punjab, Haryana and Uttar Pradesh to formulate a plan to purchase stubble, ensure it is not burnt anymore, and make the entire state administration responsible to combat air pollution. It had also ordered Punjab, Haryana and Uttar Pradesh to pay small and marginal farmers an incentive of Rs 100 per quintal to handle the residue of non-Basmati rice crops.

On October 16, the Supreme Court appointed retired judge Madan B Lokur to lead a committee monitoring instances of stubble burning in Haryana, Punjab and Uttar Pradesh. TheDelhi Pollution Control Committee, meanwhile, banned the use of electricity generator sets of all capacities – whether running on diesel, petrol or kerosene – in the Capital.

The Graded Response Action Plan also recommends sprinkling water on roads, frequent cleaning of roads, maximising the use of natural gas for power generation and shutting down stone crushers, brick kilns and hot mix plants when the air quality enters the extreme category.