Ahead of the G20 Summit, pro-Khalistan messages were found in at least five Delhi Metro stations, officials said on Sunday.
A senior police officer said unidentified people wrote ''Delhi Banega Khalistan" and "Khalistan Zindabad'' on the walls of at least five Delhi Metro stations.
Legal action is being taken, the officer said, adding that the CCTV camera footage of the areas near the five metro stations is being analysed to identify the culprits.
A purported video was released by the banned outfit Sikhs for Justice which showed the defaced walls of the metro stations.
Gurpatwant Singh Pannun, spokesperson for the SFJ, 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."
The Delhi Metro Rail Corporation said the issue has been reported to the concerned law and order agencies.
"Some objectionable graffiti has been observed on the outer walls of some of our metro stations on the Green Line. The issue has been reported to the concerned law and order agencies. All necessary cooperation is being extended to them from DMRC's side,” said Anuj Dayal, principal executive director of corporate communication of DMRC.
The alleged action comes ahead of the G20 Summit on September 9-10.
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, the police said.
The walls were painted with slogans like "Khalistan Zindabad" and "Referendum 2020". The Delhi Police's Special Cell arrested two men in connection with the incidents.
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