In one of the deadliest attacks in Turkey in recent years, two car bombs exploded near the border with Syria on Saturday, killing 46 people and wounding 51 others.
Turkish officials blamed the attack on a group linked to the Syrian regime, and a deputy prime minister called the neighboring country's intelligence service and military "the usual suspects."
The blasts, which were 15 minutes apart, raised fears that the violence of Syria's brutal civil war was crossing into its neighbor's territory.
One of the car bombs exploded outside city hall while the other went off outside the post office in the town of Reyhanlı, a main hub for Syrian refugees and opposition activity in Turkey's Hatay province, just across the border from the war-torn country.
Deputy Prime Minister Beşir Atalay said the assailants were from Turkey, but were linked to Syria's intelligence service. "We have to a great extent completed our work toward identifying the assailants," he told reporters. "We have established that the organization and assailants have links to the pro-regime al-Mukhabarat [intelligence] organization." He did not name the group.
The death toll rose throughout the day as many of the injured had been critically wounded.
A third, small blast caused panic in the town hours after the twin car bombs, but local reporters said it appeared to have come from a car engine or building's boiler room.
Images showed people frantically carrying victims through the rubble-strewn streets to safety.
Deputy Prime Minister Bülent Arınç linked the blasts that killed at least 46 and injured more than 50 to Syria. There was no immediate information on the identities or nationalities of the victims. "We know that the Syrian refugees have become a target of the Syrian regime," he said. "Reyhanlı was not chosen by coincidence."
"Our thoughts are that their mukhabarat and armed organizations are the usual suspects in the planning and carrying out of such devilish plans," he said.
Arınç said Turkey would "do whatever is necessary" if it is proven that Syria is behind the attack.
Turkey's Cihan news agency said the military began deploying a large number of air and ground military reinforcements to Reyhanlı along the border after the blasts.
In Reyhanlı, smoke poured from charred ruins after the blasts outside the administrative buildings.
"My children were so scared because it reminded them of the bombings when we were in Aleppo. God help us," said one refugee, a mother of three who gave her name as Kolsum.
Tensions ran high in the district after the blasts with locals reportedly attacking Syrian-plated cars and Syrian refugees. Recent weeks have been marked by increasing ill feelings between Turks and Syrians in the district, with at least one fight breaking out between Turkish and Syrian youth. Following the fight, the Turkish group carried Turkish flags around the city and protested the presence of the Syrians.
The United States strongly condemned the attacks and vowed support in identifying those responsible, while NATO Secretary-General Anders Fogh Rasmussen and French Foreign Minister Laurent Fabius voiced "full solidarity" with Turkey.
The US Embassy in Ankara issued a statement condemning the "murderous attack" in Reyhanlı and said Washington "stands with the people and government of Turkey to identify the perpetrators and bring them to justice."
The main Syrian opposition group, the Syrian National Coalition, condemned the attack and said it stands together with the "Turkish government and the friendly Turkish people."
The coalition sees "these heinous terrorist acts as an attempt to take revenge on the Turkish people and punish them for their honorable support for the Syrian people," it said.
Turkey's opposition criticized the government's policy on Syria, saying its active support of the opposition had put the country's security at risk.
"Erdoğan's discourse of hatred toward Assad and provocations against the administration in Damascus is coming back to us in the form of attacks and provocations," said Devlet Bahçeli, chairman of a nationalist opposition party.
The force of Saturday's explosions gutted some buildings, and the charred shells of cars littered the streets.
"Three buildings partly collapsed and became unusable," Talat Karaca, who witnessed the second explosion from his rooftop, told The Associated Press by telephone. "We couldn't approach the scene for a long time because of the blaze."
Khawla Sawah, the medical director of the Union of Syrian Medical Relief Organizations in Reyhanlı, said the town's main hospital was full and many of the wounded were taken to the nearby city of Antakya and to a clinic set up by the Syrian medical relief group on Reyhanlı's outskirts. The center received 11 wounded, including one Turk and 10 Syrians.
She said some of the injured told her that the cars that exploded had Syrian license plates.
Both Sawah and another witness, Suzan Alhasoğlu, said the incident raised tension in Reyhanlı with angry youths attacking Syrians cars and other targets.
"The authorities are asking Syrians to stay home and not drive around in Syrian cars," Sawah said. "Syrian doctors at the Reyhanli hospital were asked to go home too."
Turkey's military released a statement condemning the attack while Foreign Minister Ahmet Davutoğlu vowed from Berlin that Turkey would act. "Those who for whatever reason attempt to bring the external chaos into our country will get a response," he said. Davutoğlu called the incident an act of “provocation,” saying “there may be some powers who want to sabotage peace in Turkey.”
In initial comments, Prime Minister Recep Tayyip Erdoğan condemned the attack.
“I would like to send a message to my brothers in Reyhanlı. We have recently launched a settlement process [to address the conflict in the Southeast] and those who cannot digest this new period and the atmosphere of freedom in our country may be involved in such attacks."
"Another sensitive issue is that Hatay province is on the border with Syria, and these actions may have been taken to provoke those sensitivities," he said.
Erdoğan said this week that Turkey would support a US-enforced no-fly zone in Syria and warned that Damascus had crossed President Barack Obama's "red line" on chemical weapons use long ago.
A no-fly zone to prohibit Syrian military aircraft from hitting rebel targets has been mentioned by American lawmakers as one option the United States could use to pressure Assad.
Erdoğan is due to meet Obama in Washington on May 16.
Turkish President Abdullah Gül warned citizens against provocations after the deadly Reyhanlı blasts while opposition parties urged the government to review its Syria policies.
Violence has spilled over the border before.
In February, a minibus blew up at a border crossing near Reyhanlı, killing 14 people and wounding dozens more.
The Syrian opposition said one of its delegations appeared to have been the target of that attack, but there has been no confirmation of this from the Turkish authorities.
In October, five Turkish civilians were killed in Akçakale when a mortar bomb fired from Syria landed on their house, prompting Turkey to fire back across the frontier.
Turkey is sheltering more than 300,000 Syrians, most of them in camps along the 900-kilometer frontier, and is struggling to keep up with the influx.