One person was killed and 15 others were injured when the Mohonganj Express derailed after miscreants damaged the tracks on the Joydebpur-Mymensingh rail line near Bhawal rail station in the district early Wednesday.
Two committees have been formed to investigate the train accident.
A five-member investigation committee has been formed, headed by Additional District Magistrate Humayun Kabir, by the district administration, Gazipur Deputy Commissioner Abul Fateh Mohammad Safiqul Islam said.
The district administration committee has been asked to investigate and submit its report within the next three working days, DC added.
Another seven-member investigation committee has been formed, with Divisional Signal and Telecommunication Engineer Soumik Shaon Kabir as its head, by the Bangladesh Railways, which will submit its findings in three days, Dhaka Divisional Railway Manager of Bangladesh Railway Sofiqur Rahman said.
"We have initially confirmed that the incident was an act of sabotage," Rahman said.
Seven coaches of the Dhaka-bound Mohonganj Express derailed near the Bhawal railway station after parts of the rail track were uprooted and one person was killed, he added.