Michelle Homer and Emily Reaux

KHOU-TV, Houston

HOUSTON - Desperate flood victims all over the Houston area are taking to Twitter to plead for help after a night of torrential rains while 911 was inundated.

"I have 2 children with me and the water is swallowing us up," one woman tweeted.

It was retweeted more than 1,000 times. Two hours later, she tweeted that they were safe.

Last count, officials had assisted in over 500 rescues overnight, said Houston Police Chief Art Acevedo said. Many people are reportedly trapped.

Officials are warning residents to not get into their attics to avoid rising floodwaters. Acevedo tweeted, "we have reports of people getting into attic to escape floodwater. Do not do so unless you have an ax or means to break through onto your roof.

A man named David tweeted, "Urgent water rescue needed now ... cancer patient with feeding tube."

Another man asked for help for his family located in southeast Houston. The Houston Police Department responded saying their dispatch had the call.

And several people tweeted about a "lady in labor in her attic alone because her house has taken on water."

Sheriff Ed Gonzalez replied to as many people as he could, telling them help would be there as soon as possible. He also retweeted asking for help from other agencies, including for the woman in labor.

He later tweeted that the woman was being transported by ambulance.

Hundreds of first responders are risking their own lives as they spread out across the area to answer the calls for help.

The City of Houston tweeted at 4:43 a.m. Sunday saying their 911 services were at capacity and asked for those who can shelter in place, to please do so.

They say their dispatchers are overwhelmed with the number of calls coming in. Officials are pleading with everyone to not call 911 unless your life is in danger.

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