July 20: The Syrian conflict spreads into Turkey when an attack in mainly Kurdish town of Suruc kills 32. Turkish President Recep Tayyip Erdogan speaks of an “act of terror.”

July 22: The Kurdistan Workers Party (PKK) claims the killing of 2 Turkish cops in Ceylanpinar in revenge for the Suruc massacre.

July 23: Militants inside Syria attack a Turkish Army border post in the Kilis region, killing an officer. In Diyarbakir, a majority Kurdish city in Turkey, gunmen kill a Turkish cop.

July 24: Turkish F-16 jets hit Daesh targets just inside Syria for the first time, killing nine militants. Late in the day, airstrikes also target PKK militants in northern Iraq. Suspected extremists arrested in dawn raids in Istanbul and other cities. Erdogan confirms that Turkey will let Washington use the strategic Incirlik airbase for strikes against Daesh.

July 25: Turkish air strikes intensify against Daesh in Syria and PKK in Iraq. A car bomb attack kills two Turkish soldiers in southeast Turkey.

July 26: “Turkey has a right to take action related to terrorist targets,” a US official says as Ankara launches F-16 attacks for the third day, striking PKK in northern Iraq. Ankara asks for an extraordinary NATO meeting to discuss its cross-border offensive, but has not asked for help, the group’s chief says.

July 27: Turkish tanks pound a Kurdish-held village in northern Syria. Turkish planes will take an active part in anti-Daesh airstrikes, foreign minister says, adding that the offensive could “change the balance” in the region.

PKK seizes Sarrin, northern Syria from Daesh, cutting a key supply line, the Syrian monitor says.