There are reports that 20 of the dead are children. They include children who were hiding in their school in the suburb of Moore when the tornado struck at around 3pm on Monday.
The Salvation Army USA is mobilising disaster response units to serve in Moore and other devastated neighbourhoods in and around Oklahoma City.
In Lincon and Cleveland Counties, Salvation Army canteens have been providing breakfasts, lunch and dinner to residents and emergency service personnel.
One Salvationist was responding in Cleveland County despite their own family home being destroyed in the disaster.
"The Salvation Army is calling on everyone to pray for all of those impacted by the devastating tornadoes in Oklahoma," said Major Steve Morris, Divisional Commander of the Arkansas-Oklahoma Division of The Salvation Army.
The BGEA has deployed a team of crisis-trained chaplains to Moore.
"Our hearts are breaking for all of those in the path of this horrific tornado. Words can't do justice to the pain that is being experienced in and around Moore," said Jack Munday, international director of the Billy Graham Rapid Response Team
"Please pray continuously for all of those who lost loved ones, and for those who may still be trapped amidst the rubble."
In the General Assembly of the Church of Scotland meeting today in Edinburgh, prayers were offered by the Moderator the Right Reverend Lorna Hood for victims.
She asked that God would comfort grieving families and work through the responding agencies to "bring that touch, that healing to wipe away their tears, to bring that peace and most of all to know that you are with them and you will be close".