ISTANBUL (Reuters) - Turkey’s military has carried out two air strikes in northern Iraq, killing those behind the death of a diplomat in an attack last week, a security source said on Thursday.

At least two people, including the diplomat, were shot dead when a gunman opened fire in a restaurant where Turkish diplomats were dining in the Iraqi Kurdish regional capital of Erbil.

The first air strike was carried out on Iraq’s Dohuk region on July 18, a day after the attack, and the second strike was carried out in the Batufa region on Wednesday, the source said, adding that they targeted the planners of the killing of the diplomat.

Footage on broadcaster CNN Turk showed two cars that it said were destroyed during the air strikes, adding that it was a joint operation with Turkey’s National Intelligence Agency.

It was not immediately clear how many people had been hit by the air strikes or how many people had planned the attack. CNN Turk said two planners of the attack and their guards had been tracked since they left Erbil.

Security services in Iraq’s semi-autonomous Kurdish region said on Saturday they had arrested the brother of a lawmaker from the pro-Kurdish People’s Democratic Party (HDP) serving in the Turkish parliament on suspicion of planning the killing. The HDP has condemned the attack on the diplomat.

The shooting took place weeks after Turkey launched a new military offensive against Kurdish separatist militants based in northern Iraq.

The outlawed Kurdistan Workers Party (PKK), which has led an insurgency against the Turkish state since the 1980s, has fighters based in northern Iraq, mainly in the Qandil region, north of Erbil.

Duhok and Batifa regions, where the two strikes were carried out, are located northwest of Erbil.

Turkey and the ruling Kurdish party in Erbil, the KDP, have blamed the PKK for other Turkey-related incidents in northern Iraq including the storming of a Turkish military camp earlier this year.