The Delhi Police has detained two persons in connection with writing pro-Khalistan messages on the walls of at least five Delhi Metro stations ahead of the G20 Summit, officials said on Thursday.

Police spokesperson Suman Nalwa said the two persons were detained from Punjab by the Delhi Police's Special Cell. Another officer said that their interrogation was underway. Pro-Khalistan messages -- "Delhi Banega Khalistan" and "Khalistan Zindabad" -- were found on the walls of Shivaji Park, Madipur, Paschim Vihar, Udyog Nagar, and Maharaja Surajmal Stadium metro stadiums on August 27. A wall of a government school in Nangloi was also found defaced.

A purported video was released by the banned outfit Sikhs for Justice (SFJ) which showed the defaced walls of the metro stations.

Gurpatwant Singh Pannun, spokesperson for the SFJ, had said in the video, "G20 nations, when you will be meeting in Delhi on September 10, we will be organising a Khalistan referendum in Canada." On January 19, ahead of the Republic Day, "anti-national" and "Khalistan-related” graffiti appeared on walls in some areas of west Delhi, including Vikaspuri, Janakpuri, Paschim Vihar, and Peeragarhi, police said.

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