"We got to know that the Twitter handle has been deleted. We have initiated a probe into the matter, starting with tracking the handler, who can also be charged with sedition in view of the contents posted," a senior officer said.

Special Commissioner of Police (Operations) Sundari Nanda, who monitors Delhi Police's Twitter handles, said, "When the tweet was brought to our notice, we, as a law enforcement agency, issued the alert based on its content which was found to be anti-national."

"We checked the particular Twitter handle and most of its tweets and activities on the micro-blogging site were found to be anti-national. No matter who the handler was, the content was threatening, especially in the backdrop of the ongoing agitation at JNU," she said.

The alert was issued by one of Delhi Police's official twitter handles on Friday, on which it said, "This is to alert and sensitise the student community in JNU and across the country. Do not get carried away by such seditious anti-national rhetoric. Abetment of any kind of anti-national activity is a punishable offence."

In the alert, Delhi Police had also pinned a tweet posted on Wednesday by the handle -- #HafeezSaeedJUD, which says, "We request our Pakistani brothers to trend #SupportJNU for our pro-Pakistani JNUite brothers."

Twitterati criticised Delhi Police, alleging that it issued an alert without verifying the source of the pinned tweet. Earlier today, Union Home Minister Rajnath Singh said that the JNU stir received support from Lashkar-e-Taiba founder Saeed and this needs to be understood by the nation.