India, Nov. 26 -- Delhi Police have seized the mobile phones of the 22 students arrested after Sunday's protest at India Gate and are now scrutinising messages exchanged on a week-old WhatsApp group to probe what they described as a planned "conspiracy" behind the clashes.

The violence erupted after groups of mostly students gathered to demonstrate against rising air pollution levels. Clashes broke out when police attempted to disperse the gathering, alleging that the protesters blocked a road and used chilli spray against personnel.

"Since all the students are in judicial custody, we have their phones and have begun examining their social media groups," a senior police officer said. "Protesters from organisations such as Himkhand and B...