People stand next to a 24.9 metre (82 feet) diametre pit at a village in Guangyuan, Sichuan province, February 28, 2013. According to local media the pit formed on a karst landform last year after the ground surface kept sinking for six days in September. The investigators said the pit may face further sinking after rains due to its geological conditions. REUTERS/Stringer
Cars are seen in a large sinkhole on a street in Rome, Italy February 16, 2018.
A worker inspects a sinkhole that appeared after heavy rain outside a property located near Australian Prime Minister Malcolm Turnbull's residence in Sydney, Australia, February 8, 2017.
Rescue workers carry out the body of a victim in a road cave-in accident in this picture taken through a security window in Shenzhen, Guangdong province May 21, 2013.
People look at a large sinkhole on a street after a water pipe broke underneath it in Xi'an, Shaanxi province October 27, 2013. According to local media, the pipe was damaged due to aging and no casualty was reported in the incident. Picture taken October 27, 2013. REUTERS/Stringer
People look at a loaded truck that got stuck in a sinkhole on a road in Guilin, Guangxi Zhuang Autonomous Region, January 7, 2015. No injury was reported, according to local media. Picture taken January 7, 2015.
Policemen check a collapsed section of a crossroad in Hefei, Anhui province August 8, 2009. A taxi and a few motorbikes fell into the hole, local media reported. REUTERS/China Daily
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 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/Handout
An aerial view of the damaged Gran Marical de Ayacucho highway in the state of Miranda outside Caracas December 1, 2010. Thousands of Venezuelans fled their homes after landslides and swollen rivers killed at least 21 people and threatened to cause more damage. REUTERS/Miranda Government/Handout
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/Stringer
A section of the Summer Bay Resort lies collapsed after a large sinkhole opened on the property's grounds in Clermont, Florida August 12, 2013. Dozens of guests at the Florida resort near Walt Disney World were evacuated early Monday, when at least two buildings partially collapsed due to the sinkhole, guests and resort employees said. REUTERS/David Manning
A construction vehicle lies where it was swallowed by a sinkhole on Saint-Catherine Street in downtown Montreal, August 5, 2013. REUTERS/Christinne Muschi
People look at a collapsed section of Shunwai Road in Nanchang, China's Jiangxi province, April 25, 2007. No one was injured in the accident and further investigations are underway, according to local media. Picture taken April 25, 2007. REUTERS/China Daily
Emergency workers look at a large sinkhole in Ottawa, Ontario, Canada, June 8, 2016.
The collapsed area of a cycle lane is seen on Sao Conrado beach after heavy rains in Rio de Janeiro, Brazil February 15, 2018.
Giant sinkholes
Sinkholes can be deadly -- swallowing residents and damaging infrastructure.