A suicide car bomb killed at least 34 people and wounded 125 more in in the heart of Ankara on March 13, less than a month after a similar attack on a bus carrying military and civilian personnel killed 29 in the same area, plunging the country further into chaos.

There was no immediate claim of responsibility, but senior security officials told Reuters that the first findings suggested that the Kurdistan Workers Party (PKK), or an affiliated group, carried out the attack.

The blast that occurred at around 6:45pm near government buildings and military headquarters in Ankara’s central Kizilay district was so powerful it could be heard several kilometres away.

Turkey, once seen as a beacon of stability and democracy in the Middle East, is now facing multiple security threats. It is battling against the PKK in the country’s southeast and fighting Islamic State in Northern Syria and Iraq.

The Kurdish Freedom Hawks (TAK), a splinter group of the PKK, claimed responsibility for the suicide car bombing in Ankara on February 17 that killed 28 people. The group said the bombing was in retaliation for the government’s policies in the country’s mostly Kurdish-populated southeast.

Islamic State militants have also carried out several deadly attacks in Turkey since last year. A suicide bomb attack in the town of Suruc, near the Syrian border, killed at least 30 in July 2015. Islamic State militants targeted a peace rally in Ankara in October 2015, killing more than 100 people.

At least 10 German tourists were killed in a suicide bomb attack, also blamed on Islamic State, in January this year in the Sultanahmet district, one of Istanbul’s major tourist attractions.

“These attacks that threaten our country's integrity and our nation's unity and solidarity do not weaken our resolve in fighting terrorism, but bolster our determination," President Recep Tayyip Erdogan said in a statement.

Turkish Interior Minister Efkan Ala said on March 13 that significant findings were made and the government could announce the name of the organisation behind the attack on March 14

The government immediately imposed a ban on media coverage of the Ankara blast. The country’s telecommunications authority also temporarily blocked access to social media after images from the scene started to circulate on Twitter and Facebook.

The latest attack raises serious questions about possible security lapses. Two days before the explosion, the US embassy in Ankara warned of a terrorist plot against Turkish government buildings in Ankara. But, as in the previous attacks, the Turkish authorities have denied any shortcomings.

The other concern is that the government could use the Ankara attack as a pretext to tighten the screws on its opponents, especially on parliament's pro-Kurdish party HDP. Erdogan and the government see the HDP as an extension of the PKK. The government is currently seeking to lift the immunity of several prominent HDP deputies, including its co-chairs Selahattin Demirtas and Figen Yuksekdag. The HDP condemned the attack: these painful events will not destroy the brotherly ties of our people, the party said in a statement.