Turkish and KDP victory Turkey:114 killed, 338 wounded[7] 1 AH-1W Super Cobra[8] KDP:~200 killed[9] Operation Hammer (Turkish: Çekiç Harekâtı) was the largest cross-border operation done in the history of Turkish Armed Forces into northern Iraq between 12 May and 7 July 1997 against the Kurdistan Workers' Party (PKK).

The operation's objectives were to destroy PKK units in northern Iraq, to strengthen Massoud Barzani's Kurdistan Democratic Party in its ongoing Civil War with Jalal Talabani's Patriotic Union of Kurdistan in the hope that the KDP would prevent further PKK raids into Turkey, and to counter Iranian influence in the region as Turkey accused Iran of supporting the PKK, and over 2,000 Iranian forces had entered Iraqi Kurdistan that year to aid the PUK.

[10] Some 30[11]–50,000[1] Turkish forces entered Iraq on 14 May in response to an appeal by the Kurdistan Democratic Party for support in its offensive against the PKK.

In response the PKK ordered four suicide bombings from 1 to 11 June which resulted in the death of 55 KDP fighters.

[9] The operation drew strong condemnation from Iraq, Iran and Syria.