The body of the unidentified woman, aged around 30, was found stuffed in the bag at the CST railway station on the morning of September 26, with strangle marks, police said.
The postmortem report indicated the victim was strangled to death and was assaulted before she was killed.
The CCTV footages released to the media show the two accused (aged between 25-30 years), who appeared tense standing with the bag on the railway platform for a while before rushing away from there, police said.
The duo alighted from the Pune-Mumbai Sinhagad Express, pulling the trolley bag, they said.
The visuals show a policeman passed off the two while they were preparing to abandon the bag.
The movements of the duo were caught in 4-5 CCTVs, although the faces were not clearly seen.
Police suspect that the accused might have boarded the train either in Thane, Pune or Raigadh.
Cops were verifying if any missing persons' complaint was registered in police stations of the city or neighbouring cities. So far about 300 people have been quizzed in connection with the case but in vain, police said.