Diners at a Londonderry cafe were left shaken after a man grabbed a knife and ran after another man.
Staff at the Foyle Street cafe confirmed that the incident happened yesterday afternoon.
It is understood the culprit threw a chair at another man and grabbed the knife from a cutlery drawer.
One diner described how he pushed children against a wall as the man brandishing the knife pursued the other man out into the busy street.
Speaking on radio today, he said: "Everybody seemed to stand back and watch. People were a bit worried.
"I kept pushing the kids back against the wall and you could see the shock on people's faces inside. They couldn't believe what was going on."
The man, visiting from the Republic with his 14-year-old daughter and 10-year-old son, added: "He was pretty serious chasing that guy. He seemed pretty intent on catching him. "
Police said they had not received any reports of the incident.