Unidentified persons sneaked into the College of Medicine & JNM Hospital’s academic campus in Kalyani on Friday night and ransacked an auditorium, damaged its ceiling and acoustic system, vandalised washrooms and cut off cables despite round-the-clock surveillance by three security agencies at the sprawling premises.

Preliminary probe revealed that the goons broke a window to enter the auditorium.

The incident prompted nearly 250 junior doctors, interns and four batches of MBBS students to demonstrate in front of the college’s administrative building for an indefinite period from Saturday morning demanding security arrangements by the West Bengal University of Health Sciences, which controls the medical college.

Kalyani police have begun a probe on the basis of a complaint lodged by college authorities, but no arrests were made till Saturday evening.

Sources said the investigation was “thwarted” by the absence of CCTV footage.

Aggrieved students boycotted classes and continued the protests on a relay basis without disrupting patient services, suspecting a “sabotage”. They also raised questions about the role of security agencies and submitted a memorandum to college authorities demanding an investigation and a police outpost on the campus.

“We suspect a conspiracy behind the incident. The motive of the miscreants was not theft. They wanted to damage properties of the college which students regularly use.

The goons might attack students. The security personnel had no idea about the damage. The vandalism came to light when college staff saw it on Saturday morning,” Salman Halder, a final-year MBBS student and students’ union secretary, said.

Agitating students claimed that their suspicion about possible foul play was confirmed after a fire broke out in a room adjacent to the emergency unit of the hospital on three consecutive occasions early this month under “mysterious circumstances”.

“Recovery of suspected inflammable items from the same spot to a lot of things. Police also nabbed two persons. We have decided to continue the demonstration until the administration makes a permanent solution,” Salman said.

Medical superintendent Avijit Mukherjee told The Telegraph: “I fully support the students. Security has become a matter of concern in the hospital and at the academic campus.”

Sources said the college authorities had sought approval to issue a showcause notice to the private security service in charge of the auditorium.

In a related development, a team of the health department's education wing will likely visit the academic hospital and college campus to talk to the students regarding a solution.