The police also arrested another person from Kokrajhar district on the charge of posting objectionable pictures of Prime Minister Narendra Modi and Union Home Minister Amit Shah on social media.
A senior official of the Guwahati Police said they came to know about the post of the research scholar, Rehna Sultana, after a local news portal published it on Wednesday, and registered a case against her under the Information Technology Act.
"I do not know why the news portal published the news now. The portal claimed that Sultana posted it during the Eid on Monday. But that is wrong, it is an old post," the senior official said on condition of anonymity.
He said Sultana is unlikely to be arrested and only a routine investigation will be carried out as cognizance cannot be taken for such an old incident.
The original post was published in June, 2017 and it was related to eating beef.
When contacted, Sultana said, "It was posted on the day of India-Pakistan cricket match in June 2017. Virat Kohli was out for zero on that day. I am a cricket fan and was very sad. I had uploaded the post out of frustration on the performance of Indian team.
"However, I accept that I should not have given that post. That is why I had deleted the post within minutes of uploading it," she said.
Sultana said she suspects that the issue was dug up since she helps people of the minority community in their work related to the National Register of Citizens (NRC).
"I work for the genuine people for their inclusion in the NRC. Recently I helped them during hearing. I suspect this issue has been raked up to demoralise me for my stand in NRC,"
Meanwhile, the police arrested one person from Kokrajhar district on Tuesday night for allegedly posting objectionable and derogatory pictures of the prime Minister and the Union home minister.
Kokrajhar SP Rajen Singh said he was arrested from Singimari village under Fakiragram police station limits.
Police seized one mobile phone and two SIM cards from his possession.