MUZAFFARABAD, Pakistan - Heavy rain and snow buffeted Pakistan's earthquake-hit areas for a second day Monday, grounding helicopter aid flights and blocking roads as doctors reported increasing respiratory infections among survivors.

Aid workers have warned that cold weather in the Himalayan foothills, where temperatures have already fallen below freezing, may claim more lives after the Oct. 8 magnitude-7.6 quake left about 87,000 dead and 3.5 million homeless.

Poor visibility forced a suspension of flights by helicopters from the U.N., foreign militaries and Pakistan's army, which have been delivering winterized tents, clothes, food and other provisions to survivors, said Maj. Farooq Nasir, a Pakistani army spokesman.

"As long as the weather is bad, relief supplies will be affected because helicopters cannot fly," he said.

He said the army will try using trucks to deliver relief goods, although mudslides and snow have made some roads impassable.

The road to the isolated Neelum Valley, which suffered heavy quake damage, was among those closed, he said.

There were conflicting reports about major roads leading to Muzaffarabad, the main city in the Pakistan-administered part of Kashmir and supply center for the quake relief operation.

Nasir said they remained open, but aid workers said they were either blocked or hazardous.

A road to the town of Chakothi, on the disputed frontier between the Kashmir's Pakistani- and Indian-administered sections, was blocked by a landslide about 10 miles from Muzaffarabad, according to an Associated Press reporter on the scene.

Larry Hollingworth, the U.N. deputy humanitarian coordinator, said the harsh weather had forced 100 families to move from the mountains to a Mira camp near Battagram town in Pakistan's North West Frontier Province on Sunday.

He said tents were damp, and aid workers were distributing high-protein foods and warm clothes to children.

"It's what we have been fearing all along," Hollingworth said by phone from Battagram. "The winter is now with us."

The U.N. estimates 2.5 million people are living in tents below 5,000 feet, while up to 400,000 others are higher — where it's feared that snow and rain will make it harder to reach them.

Former soldier Mumta Khan, 65, said a large tent school and some makeshift toilets had collapsed under the weight of snow in a Muzaffarabad camp, but no one was hurt.

Cold rain and intermittent snow pelted the quake zone Monday. Pakistan's Meteorological Department forecast more, with strong, chilly winds and freezing temperatures for the next two days.

Temperatures will likely dip to 21 degrees in the plains, and to 7 degrees in the mountains, the department said.

Kashmir and northwestern Pakistan have had least two feet of snow since Saturday, it said.

Heavy snow blanketed Muzaffarabad Sunday evening. Residents said roads to the higher mountains were blocked by vehicles stuck in snow.

No deaths due to the cold have been reported. Workers at a Muzaffarabad field hospital said 249 patients were treated Sunday for cold-related illnesses, 30 percent of them with respiratory tract infections.

Seven of the patients had "severe chest infection," an early sign of pneumonia, said Dr. Hafiz-ur Rahman.

"If better conditions are not provided in the tents, there could be another disaster," he said.

By ZARAR KHAN, Associated Press Writer