Singer Leona Lewis cancelled a visit to Germany as she recovered from being punched in the head at a book signing for fans.

The 24-year-old had been due to fly out for a day-long promotional trip, but pulled out in the aftermath of the incident.

Former X Factor winner Lewis had been signing copies of her autobiography at Waterstone’s Piccadilly in London on Wednesday afternoon, when a man in the queue suddenly lashed out. She was left “shaken”.

Police arrested a 29-year-old man at the scene.

Her spokesman said: “Leona was due to go to Germany for promo but that has now been cancelled. Leona is obviously shocked after yesterday (Wednesday) but is OK.”

Rehearsals for her first major UK show are due to begin next week and it is understood Lewis is planning to press ahead with them. She is due to play the Hackney Empire next month.

Lewis was taken to see a doctor as a precaution after being struck, but needed no further treatment. Witnesses said she had been happily signing for around 90 minutes when a man whose book she autographed suddenly punched her in the side of the head.

Her spokesman, who was at the signing, did not hear the man say anything to Lewis during the “unprovoked” incident and security officers swooped in. He was seen laughing immediately afterwards.

Lewis was said to be “gutted” she had not been able to finish the signing session. Her spokesman said that hitting a woman was “beyond cowardly”.

Before the signing session for her book called Dreams, Lewis posed for photographs and spoke to reporters. Interviewed by the Press Association, she said she was pleased to see so many fans in the queue. “I am so glad at the turnout,” she said. “It’s amazing. I can’t believe people are coming to support and I am just very thankful.”