Here's what the ITPB says. The rain and flood situation in Uttarakhand is quite serious and unprecedented, chief of the Indo-Tibetan Border Police today said in New Delhi.

DG Ajay Chadha said rescue operations will gather pace as the weather has improved today and three battalions of the force (about 3,000 troops) deployed in the state have rescued thousands of people.

"Things are quite unprecedented in Uttarakhand. Situation is grim and quite serious. A number of factors have contributed to this situation like avalanche, cloud burst and continuous rains," Chadha said before leaving for an aerial review of the state along with Union Home Secretary R K Singh and other ministry officials.

About 4,000 people have been rescued by the force from the Govindghat area, he said. He said it would be difficult to give an exact number as to how many people have been stranded and rescued as a number of agencies are operating. Additional reinforcements are ready, if required, for Uttarakhand or Himachal Pradesh where the situation is "not so serious".

The PM and Sonia Gandhi have reached Uttarakhand for an aerial survey of Uttarakhand.