Turkish President Recep Tayyip Erdogan said the IS extremist group was the "likely perpetrator" of the bomb attack, the deadliest in 2016, in Gaziantep late Saturday that targeted a celebration attended by many Kurds.
The remains of a suicide vest were found at the scene, the chief prosecutor's office said in a statement on Sunday, broadcaster CNN-Turk reported.
Three dead, 120 wounded in eastern Turkey police HQ attack
The explosion was the latest attack to rock the key NATO member in a horrific year that has seen strikes blamed on Kurdish and Islamist militants as well as a bloody July 15 botched coup.
Gaziantep governor Ali Yerlikaya said in a statement that 50 people had been killed, raising a previous toll of 30. He had previously said 94 were wounded in what he described as an "abhorrent terror bomb attack on a wedding".
Erdogan said in a statement there was "no difference" between the group of US-based preacher Fethullah Gulen whom he blames for the failed coup bid, the outlawed Kurdistan Workers Party (PKK) "and Daesh (IS), the likely perpetrator of the attack in Gaziantep".
"Our country and our nation have again only one message to those who attack us - you will not succeed!" he said.
Security Meeting at Tarabya Mansion https://t.co/DZvqHVzmYA
— Presidency of the Republic of Türkiye (@trpresidency) August 20, 2016
Pakistan ranks third on list of countries with worst reputation
World leaders quickly condemned the attack including French President Francois Hollande who denounced the "vile" incident.
"France stands with all who fight against the scourge of terrorism," the presidency said in a statement.
The US ambassador to Turkey John Bass condemned the "barbaric attack on innocent civilians", adding that Washington would "continue to work closely together to defeat the common threat of terrorism" in a statement shared on the official US embassy in Turkey Twitter account.
Reports said the wedding had a strong Kurdish presence.
The Dogan news agency said the bride and groom were from the mainly Kurdish region of Siirt further to the east and had themselves been uprooted due to the flare-up in violence with Kurdish militants.
The pro-Kurdish Peoples' Democratic Party (HDP) said its members had been present at the wedding which was also attended by many women and children.
The Hurriyet daily said the bride and groom - Besna and Nurettin Akdogan - were in hospital but their lives were not in danger.
US to send delegation to Turkey for Gulen probe
Erdogan said the aim of such attacks was to sow division between different groups in Turkey including Arabs, Kurds and Turkmen and to "spread incitement along ethnic and religious lines".
Many militants see Kurds as one of their main enemies, with Kurdish militias playing a significant role in the fight against IS on the ground in Syria.
Prime Minister Binali Yildirim said Gaziantep would show the same spirit it had shown in 1921, when it defeated French forces in Turkey's Independence War which led to the word Gazi (war hero) being added to its original name of Antep.
"Our grief is great, but be sure our unity and togetherness will defeat all these diabolic attacks," he said.
Mehmet Erdogan, a ruling Justice and Development Party (AKP) lawmaker for Gaziantep said there was a "high possibility" it was a suicide attack, comments echoed by Deputy Prime Minister Mehmet Simsek.
Dogan news agency said the suicide bomber had mixed in with the guests before detonating the charge. Security forces are now searching for two individuals who entered the celebration with the suspected bomber and then fled, it added.
Gulser Ates, who was wounded in the attack, told Hurriyet the attack took place as the party was breaking up.
"We were sitting on chairs, having a chat with one of our neighbours.
"During the explosion, the neighbour died on top of me. I remember being underneath. If my neighbour hadn't fallen on top of me, I would have died," she said.
"The bride and groom's happiest day was poisoned."
Another resident in Gaziantep told Dogan that when he arrived, he saw many dead bodies and body parts including a "head, arm, hand scattered on the ground".
Meanwhile, images on broadcaster CNN-Turk showed rows of coffins covered in white sheets for the funerals of some of those killed.
Crowds of mourners gathered to pray, and chants of Allahu Akbar ("God is greatest") could be heard.
A major city lying just 60 kilometres (37 miles) north of the Syrian border, Gaziantep has become a hub for Syrians fleeing the civil war in their country.
But as well as refugees and opposition activists, there have long been fears it was home to a significant extremist presence.
Images from the scene showed bodies covered in white sheets while distraught relatives of the victims were comforted in the street.
As has been the case in previous attacks, Turkey's broadcasting regulator RTUK banned broadcast of footage from the scene of the attack.
IS suicide bombers have carried out attacks in Istanbul several times this year, while Kurdish militants have hit targets in both Ankara and Istanbul.
On Thursday, 12 people were killed in three bombings blamed on the PKK, who Erdogan said had killed 70 members of the security forces in the last month alone.
The blast in Gaziantep came just hours after Yildirim said Ankara would in the next six months play a "more active" role in efforts to solve the Syrian civil war.
Turkey was long accused of turning a blind eye to or even abetting the rise of IS in Syria, claims it vehemently denies. But Ankara has taken a tougher line since the start of jihadist attacks on its soil.
Suicide bomber in Turkish wedding attack was 12-14 years old
The suicide bomber who attacked the wedding party was a child between the ages of 12 and 14, President Erdogan said.
In comments shown live by broadcaster NTV, Erdogan also confirmed that 51 people had died in the blast, and 69 were wounded.
Seventeen of the injured were "heavily" wounded, Erdogan said.
White House condemns attack
The White House said on Sunday it condemns the attack and that Vice President Joe Biden would discuss the fight against such terrorism during his trip to Turkey this week.
"The perpetrators of this barbaric act cynically and cowardly targeted a wedding, killing dozens and leaving scores wounded," said Ned Price, a spokesperson for the White House National Security Council, in a statement.
COMMENTS (14)
Comments are moderated and generally will be posted if they are on-topic and not abusive.
For more information, please see our Comments FAQ