SEFFNER, Fla. (TheBlaze/AP) — A man was missing early Friday after a large sinkhole opened under the bedroom of a house near Tampa and his brother says the man screamed for help before he disappeared.

The 36-year-old man’s brother told rescue crews he heard a loud crash around 11 p.m. Thursday, then heard his brother screaming for help.

Florida Man in Bed Falls Into Sinkhole With Bedroom

An engineer surveys in front of a home where sinkhole opened up on Friday, March 1, 2013, in Seffner, Fla. The sinkhole is not visible from the outside of the house. (Photo: AP/Chris O’Meara)

“When he got there, there was no bedroom left,” Hillsborough County Fire Rescue spokeswoman Jessica Damico said. “There was no furniture. All he saw was a piece of the mattress sticking up.”

The brother called 911 and frantically tried to help his brother. An arriving deputy pulled the brother from the still-collapsing house.

There’s been no contact with the man since then and neighbors on both sides of the Seffner home have been evacuated.

Here is aerial footage of authorities surveying the perimeter of the house:

“We put engineering equipment into the sinkhole and didn’t see anything compatible with life,” Damico said. But Damico would not say that the man is presumed dead.

Damico said that at the surface, she estimates the sinkhole is about 30 feet across but officials say the sinkhole spreads to about 100 feet across below the surface.

“The entire house is on the sinkhole,” Damico said.

Engineers arrived at the scene later in the morning and began working to get measurements of how wide and deep the sinkhole is. From the outside, there were no cracks or visible signs of damage to the home. The front door was open, but taped off.

Florida Man in Bed Falls Into Sinkhole With Bedroom

A man screamed for help and disappeared as a large sinkhole opened under the bedroom of the house, his brother said Friday. The brother told rescue crews he heard a loud crash near midnight Thursday, then heard his brother screaming. The brother called police and frantically tried to help. An arriving deputy pulled him from the still-collapsing house. There’s been no contact with the man since then, and neighbors on both sides of the home have been evacuated. (Photo: AP/Chris O’Meara)

Janell Wheeler told the Tampa Bay Times she was inside the house with four other adults, a child and two dogs when the sinkhole opened.

“It sounded like a car hit my house,” she said.

It was dark. She remembered screams and one of her nephews rushing to rescue his brother, trapped in the debris.

Wheeler’s house was condemned. The rest of the family went to a hotel but she stayed behind with her dog, sleeping in her car.

“I just want my nephew,” she said through tears.

This regarding the still developing incident says the missing man is presumed dead:

As for sinkholes themselves, the U.S. Geological Survey describes them as common in areas where the rock below the land surface is dissolved by ground water:

As the rock dissolves, spaces and caverns develop underground. Sinkholes are dramatic because the land usually stays intact for a while until the underground spaces just get too big. If there is not enough support for the land above the spaces then a sudden collapse of the land surface can occur. These collapses can be small, as this picture shows, or they can be huge and can occur where a house or road is on top.

Florida Man in Bed Falls Into Sinkhole With Bedroom

Example of a sinkhole. (Photo: Southwest Florida Water Management District)

Florida Man in Bed Falls Into Sinkhole With Bedroom

This map shows the different types of rocks in different areas around the country that can be prone being dissolved by ground water and thus could create sinkholes. (Image: USGS)

The Tampa Bay Times recently completed a series on sinkholes in Florida, showing hundreds living in “Florida’s sinkhole alley,” which included Hernando, Pasco, Pinellas and Hillsborough counties. The Jan. 4, 2013, article by the Times focused on insurance for sinkholes and issues stemming from homeowners collecting funds but not using them for repairs.