Pope Francis and Most Revd Justin Welby are among millions praying after gunman Omar Mateen shot dozens dead at a gay nightclub in Orlando, Florida, before police shot him dead in a firefight.
A vigil (above) in memory of the victims has been held in Miami Beach.
It's now emerged 29-year-old Omar Mateen telephoned emergency services declaring allegiance to Islamic State before starting his massacre at Pulse.
Islamic State has said one of their fighters committed the atrocity, however it is believed IS inspired Omar Mateen's actions rather than directly organising them.
Omar Mateen's ex-wife has also said she had to be rescued from the marriage after he regularly beat her.
@revgregbrewer @OrlandoPolice terrible news, full of sadness for those affected, praying for all in Orlando esp. police & pastoral care
— Justin Welby ? (@JustinWelby) June 12, 2016
#PrayerForOrlando is the deepest compassionate impulse of many. If you prefer to tweet scorn at those who pray, you are a clanging cymbal.
— Archbishop Cranmer (@His_Grace) 12 June 2016
Christian, your gay or lesbian neighbor is probably really scared right now. Whatever our genuine disagreements, let's love and pray.
— Russell Moore (@drmoore) 12 June 2016
We love you Orlando. Praying Psalm 46 over you. #PrayForOrlando pic.twitter.com/FhTDR0g1CF
— Bethel Music (@bethelmusic) June 13, 2016
Literally praying for Orlando. Families, friends, and victims. Join us. pic.twitter.com/iUQ7NR98vp
— Lecrae (@lecrae) June 13, 2016
#Orlando
— Shane Claiborne (@ShaneClaiborne) June 12, 2016
Today let us grieve.
Tomorrow let's honor the victims by actually doing something about gun violence. pic.twitter.com/D4btHkZeSD
Tragic #OrlandoShooting. Young lives senselessly lost again. #Praying repose for departed, recovery for injured and comfort for families.
— Bishop Angaelos (@BishopAngaelos) June 12, 2016
Such dreadful news from Florida. Lord have mercy.
— Mike Pilavachi (@mikepilav) June 12, 2016
Being gay, I've been on the sharp end of demonisation. Will oppose attempts to demonise Muslims after #Pulse. Pray for the dead & wounded.
— Gerry Lynch (@gerrylynch) June 12, 2016
Praying for my city in the aftermath of this terrible and heartbreaking violence. #Orlando @OrlandoPolice
— Greg Brewer (@revgregbrewer) June 12, 2016
My heart and prayers are with #Orlando right now. Horrendous & heart-breaking tragedy: https://t.co/lnyipqCv9j #LGBT
— Vicky Beeching (@vickybeeching) June 12, 2016
A statement from the Vatican said: "The terrible massacre that has taken place in Orlando, with its dreadfully high number of innocent victims, has caused in Pope Francis, and in all of us, the deepest feelings of horror and condemnation, of pain and turmoil before this new manifestation of homicidal folly and senseless hatred.
"Pope Francis joins the families of the victims and all of the injured in prayer and in compassion.
"Sharing in their indescribable suffering he entrusts them to the Lord so they may find comfort.
"We all hope that ways may be found, as soon as possible, to effectively identify and contrast the causes of such terrible and absurd violence which so deeply upsets the desire for peace of the American people and of the whole of humanity."
Another 53 were injured in the Orlando Massacre, many critically.
Barack Obama, who has campaigned for stricter gun controls in the US, has condemned the murders as an "act of terror and an act of hate".
