A Turkish armed splinter group on Friday claimed responsibility for the car bombing this week in Ankara, which targeted a military convoy in the heart of the capital and killed 28 people.
The claim counters the Turkish government's allegations that Syrian Kurdish allies of the United States were behind the attack.
The Kurdistan Freedom Falcons (TAK) made the claim on the group's website, saying the bombing was retaliation for the situation in Cizre, south-eastern Turkey, where intense fighting is ongoing, leaving massive destruction in its wake.
The group warned tourists to avoid Turkey, saying: "We are not responsible for who will die in the attacks" in tourist areas.
Clashes between Turkish government forces and Kurdish militants have seen dozens killed and left tens of thousands displaced in Cizre, which remains under a strict round-the-clock military curfew.
The statement said the group would "take revenge for all the suffering of the Kurdish people" and said the attack in Ankara was against the "fascist" Turkish state.
The little-known TAK last claimed a December mortar attack on an airport in Istanbul in which one woman from the cleaning staff was killed.
The group is seen as a splinter that broke away from the banned Kurdistan Workers' Party (PKK) more than a decade ago, though some security experts claim there are still links.
Turkey has been claiming the car bomb attack, which hit a convoy of buses near major military and government buildings, was carried out by a Kurd from northern Syria who was born in 1992.
However, the TAK statement said the bomber, who died in the attack, was born in 1989 in Van in eastern Turkey.
Earlier, Syrian Kurds from the People's Protection Units (YPG), which is backed by the United States in its war against Islamic State, denied any involvement in the Ankara bombing, saying the group never hit a neighbouring state.
Turkey has insisted the YPG was behind the attack in collusion with the Syrian government. Turkey has so far arrested 20 people in connection with the bombing.
"The first thing they did after the attack was to blame us. They are inventing a pretext as they are seeking to enter Rojava," Redur Xelil, a spokesman for the YPG, told the pro-Kurdish Firat news agency. Rojava is what the Kurds call northern Syria.
Turkey has been heavily shelling YPG positions since the attack. The Kurds have claimed at least two civilians were killed in the strikes, which intensified Friday morning.
The Syrian Observatory for Human Rights, a monitoring group, described the Turkish shelling as "the heaviest ever, lasting for seven hours" in areas of Aleppo province.
In New York, the UN Security Council held consultations Friday, with Russia introducing a draft resolution calling for respect for Syria's sovereignty and territorial integrity in response to Turkey's alleged plans to send ground troops into Syria.
The draft was quickly dismissed by the United States and France, both veto-wielding members of the Security Council.
Ankara has grown increasingly worried about the YPG, noting that the group has links to the PKK. A ceasefire between Turkey and the PKK broke down in July after more than two years, setting off a cycle of violence that has claimed hundreds of lives.
Turkey is a staunch backer of Syrian rebels, who are currently collapsing in Aleppo in the face of intense Russian airstrikes. In the north of the province, near the key town of Azaz close to the Turkish border, the Kurds have seized fresh territory.
US President Barack Obama and Turkish President Recep Tayyip Erdogan telephoned late Friday.
Obama reiterated the US position that YPG forces should not seek to exploit circumstances in northern Syria to seize additional territory, and he "urged Turkey to show reciprocal restraint by ceasing artillery strikes in the area," the White House said in a statement.
The two leaders "pledged to deepen cooperation in the fight against all forms of terrorism, including the PKK" and Islamic State forces.
Earlier, the US State Department repeated its position that the YPG, which Washington has backed in Syria, is not the same as the PKK.
Turkey last year opened a military base to the US to carry out airstrikes against Islamic State, including strikes in Syria that help the YPG advance.
The YPG is receiving the backing of Russian airstrikes in western Syria and US airstrikes in the east and says it is charting out an independent course in the country.
The PKK and Turkey have been fighting an armed conflict since 1984, which has left more than 40,000 people dead. Kurds in Turkey often complain of systematic discrimination by the government and human rights abuses by the military during operations.