Turkey says it has carried out a number of air strikes on Kurdish rebels in northern Iraq, hours after a suicide blast hit the interior ministry.
The government said 20 targets were destroyed and many militants from the banned PKK rebel group "neutralised".
The PKK said Sunday morning's bombing in the capital, Ankara, was carried out by a group linked to them, a member of which blew himself up.
A second attacker was killed by police and two police officers were injured.
The Kurdistan Workers' Party (PKK) is considered a terror group in Turkey, the EU, UK and US.
Sunday's air strikes targeted caves, depots and bunkers used by the PKK, Turkey's defence ministry said.
AFP quoted it as saying the operation was "to neutralise the PKK and other terrorist elements, prevent terrorist attacks from northern Iraq against our population and our law enforcement agencies, and ensure the security of our borders".
The Kurdish news agency Rudaw said the strikes targeted Mount Qandil near the Iranian border, believed to be a PKK stronghold.
They were carried out following an explosion on Ankara's Ataturk Boulevard that happened hours before parliament was due to reconvene after a summer break.
Immortals Battalion - the group that claimed responsibility - said this is why they targeted the ministry, which is close to parliament.
The incident began at around 09:30 (06:30 GMT) when one of the attackers exited their car and threw a small explosive at the ministry building to distract security.
After this, the second attacker opened fire at guards by the ministry gate, before detonating a suicide bomb.
The first person, meanwhile, ran into the compound and was immediately shot dead by police.
Two officers were injured. One was shot in the chest and another suffered injuries in both legs and an eye.
Interior Minister Ali Yerlikaya told reporters that none of the injuries were life-threatening.
A senior Turkish security official told the BBC the attackers had hijacked their vehicle on Saturday in Kayseri, a city some 260 km (161 miles) south-east of Ankara.
They reportedly shot dead the car's driver, a 24-year-old veterinarian who was driving in the countryside.
The official said footage from security cameras from Kayseri to the Syrian border were being reviewed to determine where the suspects came from.
In his speech opening parliament, President Recep Tayyip Erdogan described the attack as "the final flutters of terrorism".
"The vile people who took aim at the peace and security of our citizens did not reach their goal and they never will," he said.
Kurdish militants have come under intense pressure by the authorities, who have jailed their leaders and conducted military operations against Kurdish bases inside Turkey and across the border in Syria and Iraq.
The PKK, which has Marxist-Leninist roots, was formed in the late 1970s and launched an armed struggle against the Turkish government in 1984, calling for an independent Kurdish state within Turkey.
In the 1990s, the PKK rolled back on its demands for an independent state, calling instead for more autonomy for the Kurds. More than 40,000 people have died in the conflict.
Fighting flared up again after a two-year-old ceasefire ended in July 2015.