Union minister General V K Singh on Thursday said all efforts are being made for an early and safe evacuation of 40 labourers trapped inside the Silkyara tunnel in this Uttarakhand district for more than four days, but the rescue operation could take two or three more days, reported news agency PTI.

"It (evacuation) can happen even sooner than that but in circumstances like this, we should keep an outer limit of two-three days so that we can deal with an obstacle if it comes," Singh told reporters after visiting the tunnel, reported PTI.