Ahead of Assembly polls, Bengal police has seized at least 22 bombs from an under-construction building in Kolkata’s Entally area.

Four owners of the building and the promoter were detained on Saturday, a police officer said.

Acting on a tip-off, Special Task Force and Kolkata Police personnel raided the building on Sir Syed Ahmed Road and seized the bombs kept in two boxes, he said.

The bombs were defused by sleuths of the Kolkata Police’s bomb disposal squad, the officer said.

He said an investigation into the incident is underway.