Transport department officials said routes connecting some of the major healthcare institutions, as well as those linking the Howrah and Sealdah railway stations, have been selected.

"The previous state government tried to run night bus services but could not sustain them. We have identified routes covering major hospitals for the benefit of those travelling to or from these facilities at night," transport minister Arjun Singh said.

The bus routes include Howrah station-airport, Ultadanga-Ecospace, Howrah station-Barrackpore, Barasat-Garia and Howrah station-Ballygunge.

"The last bus on the Howrah station-Garia route earlier departed at 8pm, while the last bus on the Barasat-Garia route left at 4.35pm. Both have now been extended to 10pm," an official said.