Istanbul (CNN) -- Turkish Prime Minister Recep Tayyip Erdogan said Friday that he regrets the deaths of 35 civilians in a military airstrike in a Kurdish area on the border with Iraq. Speaking to reporters in Istanbul, he said, "It is an unfortunate outcome. It is a sad outcome." Pledging a full investigation, he said those killed late Wednesday were smuggling cigarettes and fuel, with almost half of them below the age of 20. Erdogan said Turkey's military had been monitoring the area because it was in constant use by terrorist groups and that security forces had become suspicious because of the size of the group and number of donkeys used.
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NEW: Turkey's foreign minister says the country does not discriminate between its citizens
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Erdogan says the deaths, many of youths under 20, were "a sad outcome"
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The Turkish military airstrike killed 35 people who were smuggling cigarettes
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A Kurdish separatist group member calls for a "settling of accounts" over the deaths
In October, an attack killed 24 Turkish soldiers in the southeastern section of the country, where @placeholder borders Iraq.