US Sources are concerned next wave of attack may be deadlier in Turkey

In first hour of İstanbul Airport attack, I was able to got a hold of a source who has extensive experience in American intel community and following Turkey & regional events closely. Here what the reliable source told me in our second conversation yesterday about that Istanbul attack and what kind of threats Turkey may be facing in near future:

Full stories published in Turkish @ Haberdar and Cumhuriyet:

• US authorities are concerned that ISIS is gearing up to launch other attacks on soft targets in Turkey in coming days or weeks. US intel community believes that ISIS operatives in Turkey have capacity to pull off even bigger attacks (more deaths) than Istanbul airport attack.
• According to same source, US believes that the Airport attack was ordered from Raqqa hqs of ISIS. It was not decided by Turkey cells, networks.
• USG sources believe that ISIS sent 5 different groups into Turkey from Syria. Each has 6, 7 people like the one airport attackers who are believed to be a total of 7 people. It’s believed all of these militants are foreign nationals, not Turkish. (US relative authorities believe İlhami Balı is not Turkey emir, but Turkey-Syria border emir.) It’s believed that the Turkey Emir is an Arab, lives most likely live in Raqqa. Acc to same sources, 4 of 7 people in the airport attackers group who were involved w planning the same attack are at large. Since they know their IDs detected by Turkish security authorities bc of their earlier discovery caught on cameras, they may want to conduct their attacks soon, before they are caught. US relative authorities are afraid that these 4 people are still in Istanbul and may want to do their deadly attack within the city, soon.
• One or more of other 4 groups (w 6, 7 people each) are believed to be wanting to target Turkey’s south and western cities that are tourism cities. US authorities are concerned that these ISIS militants may attack night clubs, hotels or other soft targets in these cities, similar to recent Orlando attack. Izmir, Antalya and Mugla are some of cities believed may be targeted.
• CIA believes that ISIS militants went into Turkey from Syria within last weeks, about a month or more.
• US authorities believe none of other 30 plus ISIS militants been caught yet. It’s believed that the recent crackdowns by the Turkish police against those ISIS suspects been already on Turkish intel radar for sometime. So, USG sources believe so far these new units are not caught.
• One scenario is that ISIS may try to coordinate their next wave of attacks in Turkey, simultaneously to make even bigger impact.
• US authorities believe that the current Turkish political leadership still not caught up with ISIS threat/reality and they still do not realize how decisive ISIS to hit Turkey. Turkish leadership still thinks ISIS threat will pass and nothing much is going to happen.
• Foremost reason ISIS is decisive to hit Turkey at this time, acc to USG sources, is tightened Turkish/Syria border. Acc to estimates there were only 200 ISIS militants in last month able to go thru Syria from Turkish border, comparing to 2000s in recent past.

The United States is moving toward permanently banning families from accompanying U.S. military and civilian personnel in Turkey, reflecting worsening security conditions there, two U.S. defense sources told Berlin Reuters on June 29.