SRINAGAR, Kashmir — After nearly a week of incessant rains and flooding that have left hundreds of people dead in Pakistan and the Indian state of Jammu and Kashmir, rescue operations have been strained by the scale of the disaster and a collapse of communications networks in some areas.

In the Kashmir Valley, people have been stranded in homes, hospitals, hotels and houseboats, at schools and on highways, many going for days without food. Residents have built rafts using planks of wood with tires attached in an effort to evacuate flooded neighborhoods. Indian soldiers who would otherwise be deployed for relief work have instead stayed huddled on the second floor of an army garrison, stranded by water six feet deep.

Perhaps one of the most daunting developments in the relief effort has been the collapse of communication systems, which has hampered emergency medical workers and separated families.

“The lack of communication is a major setback because the commanding officer cannot communicate with his own team,” said Jaydeep Singh, a commanding officer with India’s National Disaster Response Force. He estimated that in Srinagar, the summer capital of Jammu and Kashmir, 70 percent of the population of nearly 1.2 million had been affected by the floods.