(CNN) "I am so sorry," says an emotional Memet Kocarslan, the owner of the Istanbul nightclub where a gunman massacred 39 people in the first minutes of 2017.

"These were my guests. I let them down. I want to do nothing but take care of my guests."

Police checks had been increased around Istanbul for the festivities, and Kocarslan had also made sure his Reina club had extra security. But he said they had no hope against a well-armed and determined killer.

Memet Kocarslan

"This gunman is unbelievable. I believe he has been fighting in war for many years. He was too professional," Kocarslan said. "How can a guy with a pistol win against a man with a war machine?"

One armed policeman was positioned outside the club, but the security officers inside had no weapons. The law in Turkey does not allow security guards to have guns.