Officials in several states urged residents, especially the elderly, to stay cool as forecasters predicted high temperatures would continue in parts of the South and the Southern Plains for another two days.

Meanwhile, the death toll from the heat wave that has baked much of the nation for nearly a week has increased, with four more deaths in the Chicago area bringing the total number there to seven, officials said.

Click here to see photos of Americans facing the heat.

So far, the heat has contributed to the deaths of at least 16 people in seven states, including two in the Philadelphia area, two in Oklahoma City, two in Arkansas and one each in Indiana, South Dakota and Tennessee.

A football player at a western Kentucky high school collapsed and died after practice Wednesday, but school officials could not say whether heat played a role in his death.

Chicago officials have asked residents to check on elderly or sick neighbors in an effort to avoid duplicating a 1995 heat wave that killed 700 people.

Three deaths in Oklahoma and Arkansas involved elderly residents and either malfunctioning or unused air conditioners.

In Oklahoma County, Okla., the heat has been blamed for the death of two people, including a 76-year-old man who died in a home with a broken air conditioner and a 62-year-old woman who died in a home where the air conditioner was turned off.

In Arkansas, a friend of a 76-year-old North Little Rock woman who was found dead in her apartment Tuesday said the woman had refused to turn on her air conditioner.

The elderly frequently refuse to run the air conditioning because of the cost, said Ann Leek, vice president of central Arkansas CareLink, which provides services for nearly 1,000 elderly people.

"Because so many of them are on fixed-income or low-income because they live alone they have that juggling act of paying rent, buying prescription drugs and running the air conditioner," Leek said.

In Omaha, Neb., the housing authority spent $25,000 to install window air conditioners in apartments used by elderly and disabled residents.

"It's a humanitarian thing," said Brad Ashford, the agency's executive director. "It got to me personally. I just felt we needed to do this."

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