Metro rail services on the Uttara-Motijheel route were suspended for about 26 minutes on Wednesday morning after a door of a moving train suddenly opened.
The suspension was imposed as a safety precaution while authorities addressed the mechanical fault.
MRT Police (Operations) Inspector Md Mohsin Sheikh confirmed the incident to media.
He said a train departing Uttara North Station for Motijheel experienced the problem when one of its rear doors suddenly opened while it was in motion.
As a precaution, metro rail services were suspended at 7:37am.
After the mechanical fault was fixed, services resumed at 8:03am, causing a 26-minute disruption on the route.
Train services are now operating normally, the inspector said.