Update 8:31 a.m. ET: 40,000 customers without power today in Oklahoma. Over half of those people are in the area in and around Moore. Power workers from 4 states are traveling in to Oklahoma today. Water treatment plant in Oklahoma City Still offline, residents are being asked to conserve water.
Update 8:00 a.m. ET: 101 people have been pulled from the rubble since Monday's tornado.
Update 7:50 a.m. ET: Some of the children who died at Plaza Towers Elementary School drowned. Officials say it was because they were in a basement that filled with water. This morning crews are scouring the rubble and twisted metal trying to find survivors of yesterday's massive tornado. The number of people who died could reach more than 90. And survivors are in complete shock of what they and their loved ones went through.
Update 7:06 a.m. ET: City of Moore Police are moving all media and satellite trucks away from the debris fields. Spokesperson says rescuers were having problems hearing victims calling for help over the sounds from power generators.
iReporters upload gripping photos and videos of the tornado and the damage left behind: Oklahoma tornado shot through local lens.
Update 3:07 a.m. ET: Oklahoma Medical Examiner's Office has been told to expect about 40 additional bodies -- 20 expected to be children.
Update 12:17 a.m. ET: The Facebook page Moore Tornado Lost and Found has been set-up to connect Oklahoma residents with loved ones concerned about their safety. Many users are also posting on the page seeking information on specific residents of Moore or other Oklahoma towns who they have not been able to reach.
Update 12:04 a.m. ET: CNN's Gary Tuchman reports there are about 24 third-graders still unaccounted for at Plaza Towers Elementary. It's likely some of those have children have shown up at area churches, but their parents don't know it yet. Tuchman says search teams are using drills and axes to cut through debris and they are "hoping for the possibility of a miracle... but don't anticipate" one.
Update 11:31 p.m. ET: Finally, a little good news: Some of the previously unaccounted for children from Plaza Towers Elementary have turned up at local churches and have been reunited with their parents. Nighttime search continues under the lights at the school, but sadly crews do not believe it's likely they will find any more survivors.
Update 11:08 p.m. ET: Mayor Glenn Lewis of Moore, Oklahoma says all students at leveled Briarwood Elementary are accounted for; city's hospital has been has been "devastated... used to be two stories and now it's one."
Update 11:02 p.m. ET: A Moore resident has posted this video of what he saw when first emerging from his below-ground storm shelter.
Update 10:45 p.m. ET: At least 20 children are now confirmed among the victims, according to Oklahoma's state medical examiner.
Update 9:14 p.m. ET: The death toll has risen to 51 as a result of the storm that hit the Oklahoma City area Monday, Oklahoma's office of the chief medical examiner said.
Update 8:40 p.m. ET: Seven children from the Plaza Towers Elementary School in Moore, Oklahoma, died as a result of a storm that devastated the school Monday, Oklahoma City Police Department spokesman Kevin Parton said.
Update 8:32 p.m. ET: Thirty-seven people have died as a result of the storm that hit the Oklahoma City area Monday, Oklahoma's office of the chief medical examiner said.
Update 8:22 p.m. ET: President Barack Obama told Oklahoma Gov. Mary Fallin the federal government "stands ready to provide all available assistance" as part of the response to a series of deadly storms that have struck the Oklahoma City area, including Monday's devastating tornado. A White House statement said the Federal Emergency Management Agency has deployed a team to assist state operations and additional personnel are ready to be dispatched as necessary.
Update 7:45 p.m. ET: About 38,000 customers of utility OG&E are without power in metropolitan Oklahoma City after Monday afternoon's storm hit the area, spokesman Brian Alford said.
Update 7:38 p.m. ET: The bodies of 10 people who died as a result of the storm that hit the Oklahoma City area Monday are being sent to Oklahoma's office of the chief medical examiner, the office's Amy Elliott told CNN.
Update 7:12 p.m. ET: CNN's Debra Goldschmidt reports that hospitals in metropolitan Oklahoma City are treating a number of people injured in the storm. Twenty people -- 12 adults and eight children -- are being treated at the Oklahoma University Medical Center and The Children's Hospital in Oklahoma City, OU Medical Center spokesman Scott Coppenbarger said. "We expect more patients to arrive this evening," Coppenbarger said.
Elsewhere, the Norman Regional Hospital and the Healthplex in Norman, Oklahoma, are treating an unspecified number of people with "signs of trauma, lacerations and broken bones," spokeswoman Melissa Herron said.
Update 7:00 p.m. ET: The bodies of six people who died as a result of the storm that hit the Oklahoma City area Monday are being sent to Oklahoma's office of the chief medical examiner, the office's Amy Elliott told CNN.
Areas of metropolitan Oklahoma City looked like a war zone Monday afternoon after a massive tornado moved through the region.
"The houses are destroyed. ... Completely leveled," a helicopter pilot for CNN affiliate KFOR said.
CNN affiliate KFOR is reporting that rescuers are searching for students trapped in debris at an elementary school in Moore, Oklahoma, heavily damaged by a tornado. There were 75 students and staff at the school when the storm hit, KFOR reported.
Congressman Tom Cole, who lives in Moore, tells CNNs Wolf Blitzer that the damage he is seeing on television looks as bad as a 1999 tornado that destroyed more than 1,000 houses in his hometown.
Moore Medical Center was evacuated after it sustained damages from the tornado, a hospital spokeswoman said. All patients are being evacuated to Norman Regional Hospital and Health Plex Hospital, and residents injured in the storm are being told to go to those centers as well.
As of 6 p.m. ET, Interstate 35 in Moore was closed as a result of debris from the tornado, Oklahoma Department of Transportation spokesman Cole Hackett said. Crews are heading to the highway to start the cleanup process, Hackett said.
The preliminary rating of damage created by the tornado is at least EF-4 (166 to 200 mph), the National Weather Service said on Monday afternoon.
Please stay tuned to HLN for the latest on the devastating severe weather.
CNN Wires contributed to this report.