"We got some water, y'all. Harvey wasn't playing," Mayor Derrick Freeman of Port Arthur, Texas, says in a video that shows knee-deep water inside his house. He's far from alone: A large shelter in the coastal city was flooded by rainfall dumped by Tropical Storm Harvey.

At least 100 people had sought refuge at the Bob Bowers Civic Center — only to see brown, murky water rush in, flooding a large space and leaving water just below the surface of cots.

That development happened overnight, as Port Arthur and other communities struggled to cope with the amount of water they received.

"Our whole city is underwater right now but we are coming! If you called, we are coming," Freeman wrote shortly after midnight, via Facebook. "Please get to higher ground if you can, but please try stay out of attics."

The city, which is about 45 miles west of where Harvey made landfall again today, says that the Carl A. Parker Multipurpose Center is now accepting people who need shelter — but it warns, "There are no supplies at the facility at this time."

As waters rose overnight, rescue workers also contended with an apartment fire and lightning, Freeman said.

"Currently the 911 system is overloaded with calls from Port Arthur," the Jefferson County Sheriff's Office said around 4:30 a.m., in a note that also told residents that water rescue operations were suspended until daylight. The agency would take calls and forward information to those who could help, it said.

"Our heart is breaking for our community and we trying to help in as many ways as possible," the sheriff's department said in a message posted shortly before midnight.

On Wednesday, Freeman used a live-streamed video on Facebook to tell residents in his city southeast of Beaumont that fire personnel, air boats, volunteers and the National Guard are working to help. Port Arthur has a population of around 55,000.

"If you're still in your home, we're coming," Freeman told residents, adding, "Again."

Many people who watched the video — and those who saw the city's other notices — responded by posting addresses and locations of people who are stranded and need help.

The city has organized dump trucks to drive through neighborhoods, instructing anyone who needs help to be on the lookout for them — and to use a white sheet or towel to signal a need for rescue.

Port Arthur also used its Facebook page to call for anyone with a boat to help, posting a note this morning that read, "Rescue boats are welcome to assist in Port Arthur."

In his video, Mayor Freeman estimated the water at his house was standing around 3-4 feet deep. Anyone calling 911 who couldn't get through, he said, would be put in a queue, as the emergency service was overwhelmed.

"But we're going to rebuild, Port Arthur," Freeman said. "This isn't the end, this is just the beginning. This is the post- and pre-moment."

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