LUCKNOW, India — Monsoon flooding that has stranded thousands of people and caused landslides in northern India has killed almost 120 people, and the prime minister said the toll could rise substantially.

The torrential rain and landslides since Sunday have stranded pilgrims at four revered Hindu shrines, washed away bridges and roads and caused other damage in Uttrakhand state.

Prime Minister Manmohan Singh said after returning from an aerial survey Wednesday that the death toll there was 102. "It is feared that the loss of life could be much higher," he said.

An additional 17 people died in collapsed homes in neighboring Uttar Pradesh state, said R.L. Vishwakarma, a state police officer.

The annual monsoon rains sustain India's agriculture but also cause flooding that claims lives and damages property.

The latest rains have affected several states and the capital, New Delhi, where nearly 2,000 people have been evacuated to government-run camps on higher ground. Authorities there said the Yamuna River was expected to start receding Thursday afternoon.

After Singh's comments, Uttrakhand's Chief Minister Vijay Bahuguna told the New Delhi Television news channel that hundreds of people have lost their lives but that the exact number would be known only after a survey.

A joint army and air force operation evacuated nearly 12,000 Hindu pilgrims stranded in the area but nearly 63,000 people remained cut off, according to Home Minister Sushilkumar Shinde. He said the flooding washed away roads and nearly two dozen bridges and demolished 365 houses and partially damaged 275 others in Uttrakhand.

A three-story apartment building toppled into a river and was carried away by the flood waters, said Amit Chandola, a Uttrakhand government spokesman, adding that a helicopter on its landing pad also was swept away. The government also said 40 small hotels on the banks of the Mandakini river in the Gaurikund area were destroyed.

Describing the situation as grim, Bahuguna said his administration was not equipped to tackle such a massive disaster, and asked for federal assistance. The region is 400 kilometers (250 miles) southwest of Lucknow, the capital of Uttar Pradesh state.

Most of those stranded in Uttrakhand are Hindu pilgrims to four revered shrines. Bahuguna said the Kedarnath temple — one of the holiest Hindu temples dedicated to Lord Shiva, located atop the Garhwal Himalayan range — had escaped major damage, but up to 10 feet (four meters) of debris covered the area around it.

"We are fully engaged in rescuing people who have been stranded in the higher reaches," Bahuguna told reporters earlier. Nearly 600 people were evacuated by air force helicopters and the rest by the army using land routes.

With the sky over Uttrakhand clearing up Wednesday, the helicopter operation concentrated on the worst-hit Kedarnath temple area, which received 380 millimeters (14 inches) of rain in the past week, nearly five times the average for that time period, said R.P.N. Singh, junior home minister.

Air force spokeswoman Priya Joshi said 22 helicopters have dropped food packets and other relief supplies in addition to ferrying stranded tourists. More than 5,000 soldiers helped bring thousands of homeless people to relief camps and provided them with food and medical supplies.