Mr Ray, 75, had raised serious questions about the conduct of the investigation.
The Kolkata Police today summoned Trinamool Congress MP Sukhendu Shekhar Ray for allegedly spreading misinformation about the details surrounding the brutal rape and murder of a post-graduate trainee doctor at the RG Kar Medical College and Hospital.
Mr Ray had claimed that a dog squad was sent to the crime scene three days after the body of the victim was found on August 9.
"The information that the sniffer dog was sent after three days is completely wrong. A sniffer dog was sent twice on August 9 and then on 12. A notice has been sent to Shri Sukhendu Sekhar Roy," the Kolkata Police said in a statement.
The summons follows closely on the heels of the Kolkata Police issuing notices to actor-turned-politician and BJP leader Locket Chatterjee and two doctors - Kunal Sarkar and Subarno Goswami - over misinformation surrounding the incident.
Read | BJP Leader, 2 Doctors Summoned Over 'Fake News' On Kolkata Rape-Murder
Mr Ray, 75, barely 12 hours ago, had raised serious questions about the conduct of the investigation and expressed his dissatisfaction with the handling of the case by calling for the custodial interrogation of both the former Principal of RG Kar Medical College, Dr Sandip Ghosh, and Kolkata Police Commissioner Vineet Goyal.
"CBI must act fairly. Custodial interrogation of Ex Principal and Police Commissioner is a must to know who and why floated suicide story. Why wall of hall demolished, who patronised Roy to be so powerful, Why sniffer dog used after 3 days. 100s of such questions. Make them speak," Mr Ray posted.
The call for Commissioner Goyal's interrogation has, however, not been universally accepted within the party. Kunal Ghosh, another prominent Trinamool leader, strongly opposed the demand.
READ | Should Kolkata Top Cop Be Interrogated? Trinamool Leaders Differ
"I also demand justice in the RG Kar case but strongly oppose this demand regarding CP. After getting the information, he has tried his best. Personally, CP was doing his job, and the investigation was in a positive focus. This kind of post is unfortunate, that too from my senior leader," Mr Ghosh said.
Mr Ray was one of the first TMC leaders to announce his participation in the nationwide midnight protest over the rape and murder. He made the announcement on X, expressing solidarity with the protesters.
"Tomorrow I am going to join the protesters, particularly because I have a daughter and little granddaughter like millions of Bengali families. We must rise to the occasion. Enough of cruelty against women. Let's resist together. Come what may," Mr Ray posted.
Mr Ray's stance, however, led to speculation about his position within the party. When questioned by a user on X about the potential consequences of his actions, including the possibility of being expelled from the Trinamool Congress, Mr Ray responded: "Please need not worry for my fate. Blood of a freedom fighter flows in my veins. I'm least bothered."
Besides the Trinamool leader, the Kolkata Police sent notices to BJP's Locket Chatterjee and two prominent doctors.