A student of a north Calcutta college was found murdered 15 minutes after being spotted with his new girlfriend and a neighbour went missing almost immediately, triggering speculation about a love triangle with an allegedly jealous ex-flame thrown into the mix.

Abhijit Dutta, 19, was stabbed in the chest near Dankuni railway station, in Hooghly, on Wednesday evening. Several people in the locality had seen the youth with his 16-year-old girlfriend, who passed her Madhyamik earlier in the day, in that very area.

Abhijit’s maternal uncle Subrata Pal discovered the body after seeing his nephew’s red bicycle abandoned in front of a closed shop adjacent to the rail track.

Pal had just alighted from a train at Dankuni station and was walking home when he spotted the cycle and suspected something was amiss.

“I stopped a motorcyclist and requested him to turn the headlight towards the spot, that was dark. As he moved the headlight, I saw Abhijit’s body lying in a field,” Pal told police.

Nakari Bhattacharya, a student of the same age as Abhijit, became the prime suspect in the murder after common acquaintances discovered that he was missing since the incident. His family members told investigators they had no idea where he was.

A police team interrogated the victim’s girlfriend throughout Thursday morning and then another girl with whom he had a relationship two years ago. Both were asked not to leave Dankuni without informing the police.

“The killing appears to be the fallout of a love affair. Whether it was a triangle or involved a fourth person will be known as we proceed with the investigation,” said additional superintendent of police (headquarters) Debasish Boral.

Abhijit was the son of a retired head law clerk of Howrah court. His mother Shikha Dutta said she had once heard her son arguing with his former girlfriend on the phone. She claimed he told her that the girl was threatening him for ending their relationship.

“It is also possible that Abhijit and Nakari were fighting over the new girl in his life. We will explore all possibilities,” one of the investigators said.

The police said Abhijit’s diary contained “lurid” descriptions of his relationship with the new girl in his life.