Uttarkashi, Nov 15 : As the rescue operation at the Uttarkashi collapsed tunnel site entered the fourth day, a fresh landslide has delayed the rescue of 40 labourers trapped in an under-construction tunnel for over 80 hours. With the assistance of the Air Force, heavy auger drilling machines are being arranged for the rescue operation. Uttarakhand DGP Ashok Kumar has stated that they will soon rescue all the workers. This machine, equipped with pipe pushing technology, will drill through the debris in the tunnel and insert a pipe of 880 to 900 mm, creating an escape passage for the workers The landslide occurred in the Silkyara tunnel during construction on Sunday morning. After the landslide, debris has spread within a radius of 60 meters. From Monday to Tuesday, approximately 25 meters of the area was cleared of debris. However, intermittent falling of debris continues, affecting relief and rescue work. On Tuesday night, around 12 a.m., drilling work with the machine began, raising hopes of rescuing the workers. The drilling for inserting the first pipe into the tunnel began. However, technical issues arose with the auger drilling machine, affecting the rescue operation. After removing the faulty machine, the work of levelling the platform for installing a new drilling machine began. However, the rescue work was affected when a fresh landslide caused debris to fall from above, causing a stampede-like situation that left one labourer injured. After this incident, those involved in the task of removing the soil and the machine operators have been given instructions to work cautiously. A portion of the under-construction tunnel between Silkyara and Dandalgaon on the Yamunotri National Highway in Uttarkashi district collapsed due to a landslide early on Sunday. Meanwhile, Prime Minister Narendra Modi is in touch with Chief Minister Pushkar Singh Dhami and is continuously taking updates from him. /IANS