Three days after the murder of Infosys employee S Swathi at the Nungambakkam railway station, sources from city police told The Times of India that she was being stalked, and the family has clarified that she was only stalked for one day in the month of May.

A police officer said that Swathi had complained to the family about a man who followed her on May 10. Gopalakrishnan used to drop and pick her up everyday from the Nungambakkam railway station. Police suspect that on Friday, the stalker followed her and pounced on her soon after Gopalakrishnan left.

“We have collected more CCTV footage from houses and shops outside the railway station. We are studying whether he made a recce before the attack,” a police officer told TOI.

On Monday, the city police took the case diary and evidence from the government railway police. An officer said that it is like starting a case from scratch and they need to study all the evidences and also look for new things, according to TOI.

Police claim that he walked on the tracks from Nungambakkam railway station to Kodambakkam station and went out through an opening on the Choolaimedu High Road. He also walked for 1.5km on Choolaimedu High Road. The city police went to the railway station and inquired with the hawkers and residents of the area on Monday.

Police have also sent out the photographs of the machete which the culprit used in the killing. Police suspect that it was made in the southern districts. They feel that once they are able to find out where the machete has been brought, they can figure out the suspect.