Lisa Wilkinson kept a cool head on air while privately seeking confirmation her son was OK.

A large truck ploughed into a Christmas market in the city’s west overnight, killing at least nine people and seriously injuring dozens more. As news trickled in early this morning — with Wilkinson live on air to report it — she was struck with instant panic: Her 21-year-old son is currently in Berlin.

“I’ve been a little distracted this morning because my son Jake is in Berlin right now,” she told viewers later in the program.

Wilkinson said she “couldn’t believe” the initial reports of violence in Berlin.Source:Channel 9

“I couldn’t believe it when that first report came through around 6 o’clock this morning — I thought, ‘Oh no’.”

With a live television show to host, the 57-year-old mother of three and wife of author Peter FitzSimons enlisted the rest of the family to help her find Jake.

“It’s the not knowing — I couldn’t get him on the phone, couldn’t get any information at all. Pete was trying him, his brother and sister were trying him, and finally we got on to him,” she explained.

Thankfully, her son was safely accounted for — he had his phone turned off.

“He wasn’t anywhere near it. He was going to go to the night markets last night, decided against it, had a sleep instead. He’s safe and well fortunately, but my heart goes out to the many, many families that are going to be affected by this.”

In Berlin, witnesses have described a “gruesome scene”.

Journalist Emma Rushton shared a picture of collapsed market stall which she said had people “crushed” underneath.

The witness, who was not affected, said those injured at the stall near where she was standing had been retrieved from under the debris.

She said the truck was driving “too fast”, around 60km/h, and showed no attempt to brake when it ploughed into crowds. Ms Rushton said the truck was “nowhere near a road”.