The Bush House in Florida
The Bush house will be demolished on Sunday 3 March (wtsp)

Authorities have confirmed that the search for Jeff Bush has been called off. Bush fell into a sinkhole that had formed beneath his house in Tampa Bay last week and has been missing ever since. The sinkhole is believed to be at least 20ft wide and 50ft deep

"We just have not been able to locate Mr. Bush, and so for that reason the rescue effort is being discontinued," Hillsborough County administrator Mike Merrill told reporters on Saturday evening, "At this point, it's really not possible to recover the body."

A warning has been issued after it was noticed the sinkhole was still expanding and that the house could collapse at any time.

Bush was alone in his room on the night of Thursday 28 February. The rest of the family were preparing to go to sleep when the floor of his bedroom collapsed. Bush's brother ran into the room, only to find him and objects from the bedroom already under the rubble.

The Florida Sinkhole Research Institute states sinkholes are caused due to acidic water running beneath the Earth's surface, which dissolves rocks and forms underground voids. Potential sinkholes can be detected by radar, seismography and electrical resistivity testing.

Detection is also possible through indicators like slumping trees, fence posts or the sudden formation of small ponds where there were none before. They can also be detected by the wilting of small circular areas of vegetation and cracks in walls.

Although sinkholes are found all over the world, the US Geological Survey points out they are particularly common in the American states of Texas, Alabama, Missouri, Kentucky, Tennessee, Pennsylvania and Florida.

Check out photographs of monstrous sinkholes from all around the world...

The Bush house will be demolished on Sunday 3 Marchwtsp
Police tape surrounds a home where a sinkhole opened up and swallowed a man in Seffner, Florida, March 1, 2013. The 36-year-old Florida man was feared dead on Friday after the sinkhole suddenly opened beneath the bedroom of his suburban Tampa home swallowing him, police and fire officials said. Rescuers responded to a 911 call late on Thursday after the man's family reported hearing a loud crash in the house and rushed to his bedroom.REUTERS/Brian Blanco
A giant sinkhole that swallowed several homes is seen in Guatemala City February 23, 2007. At least three people have been confirmed missing, officials said.REUTERS/Daniel LeClair
Sinkhole caused by recent rains is pictured in Guatemala City May 30, 2010. The remnants of Tropical Storm Agatha dumped more rain across Central America on Sunday after killing at least 17 people in the region, sparking fears of further mudslides in three countries. The hole, caused by rains from tropical storm Agatha, swallowed at least one three-storey building.REUTERS/Rodrigo Arias
A giant sinkhole caused by the rains of Tropical Storm Agatha is seen in Guatemala City May 31, 2010. More than 94,000 people have been evacuated as the storm buried homes under mud, swept away a highway bridge near Guatemala City and opened up sinkholes in the capital.REUTERS/Casa Presidencial/Hand
A giant sinkhole caused by the rains of tropical storm Agatha is seen in Guatemala City June 1, 2010. Collapsed roads and highway bridges complicated rescue efforts in Guatemala on Tuesday after Tropical Storm Agatha drenched Central America, burying homes under mud and killing at least 175 people.REUTERS/Daniel LeClair
A soldier peers over the edge of a giant sinkhole caused by the rains of Tropical Storm Agatha in Guatemala City June 2, 2010. Collapsed roads and highway bridges complicated rescue efforts in Guatemala on Tuesday after Agatha drenched Central America, burying homes under mud and killing at least 180 people.REUTERS/Daniel LeClair
Local residents look at a sinkhole near Qingquan primary school in Dachegnqiao town of Ningxiang, Hunan province June 15, 2010. The hole, 150 meters (492 feet) wide and 50 meters (164 feet) deep, has been growing since it first appeared in January and has destroyed 20 houses so far. No casualties have been reported and the reason for the appearance of the hole remains unclear, local media said.EUTERS/Stringer
A sinkhole is seen developing inside a property that houses ten families in Guatemala City June 18, 2010. The hole, which is currently two meters wide and four meters deep, is caused by a failing drainage system that has produced two other, much bigger sinkholes.REUTERS/Daniel LeClair
A sinkhole is seen developing inside a property that houses ten families in Guatemala City June 18, 2010. The hole, which is currently two meters wide and four meters deep, is caused by a failing drainage system that has produced two other, much bigger sinkholes.REUTERS/Daniel LeClair
A sinkhole filled with water is seen on the southern shores of the Dead Sea January 12, 2010, causing numerous problems for residents. Warnings continue that the Dead Sea is slowly but surely drying up, and could be gone completely in 50 years if no action is taken. The water level is dropping by close to one metre (three feet) per year. Environmentalists say more sinkholes are appearing as a result of the declining water levels.REUTERS/Ali Jarekji
car sits submerged in a street after flooding in Duluth, Minnesota, June 20, 2012. Heavy rains pounded northern Minnesota on Wednesday, forcing the evacuation of dozens of homes, causing mudslides and sinkholes, and swamping a zoo where several animals died, officials said. Picture taken June 20, 2012.REUTERS/Joe Cadotte
A sinkhole grows along Highway 129 South in Live Oak, Florida, June 27, 2012. Tropical Storm Debby weakened to a tropical depression after it drifted ashore on Florida's Gulf Coast, even as it dumped more rain on flooded areas and sent thousands of people fleeing from rising rivers.REUTERS/Phil Sears
An abandoned car stuck in an underwater sinkhole sits on Houston Avenue in Live Oak, Florida, June 27, 2012. Tropical Storm Debby weakened to a tropical depression after it drifted ashore on Florida's Gulf Coast, even as it dumped more rain on flooded areas and sent thousands of people fleeing from rising rivers.REUTERS/Phil Sears
A sinkhole which damaged an on-ramp to Interstate 15 in San Diego on February 24 continues to grow February 25. The hole was caused by a drainage pipe which burst due to heavy rains attributed to El Nino weather patterns and is approximately eight hundred feet long, forty feet wide, and seventy feet deep.Reuters
A giant sinkhole that swallowed several homes is seen in Guatemala City February 23, 2007. At least three people have been confirmed missing, officials said.REUTERS/Daniel LeClair
giant sinkhole that swallowed several homes is seen in Guatemala City February 23, 2007. At least three people have been confirmed missing, officials said.REUTERS/Stringer
A sinkhole appears on a road after floods in Hyderabad city, the capital of the the southern Indian state of Andhra Pradesh, August 25, 2000. Helicopters plucked people from flooded apartments in the inundated south Indian city of Hyderabad on Friday as the number of people killed by the heaviest rains in more than 40 years rose to 93.Reuters
An entire house and part of another lie at the bottom of a huge sinkhole which opened up in an expensive neighborhood after heavy rains here December 11. Several other homes are threatenedReuters