A skateboarding competition at the Olympic Park has been criticised after fans spotted an American knife manufacturer listed as a sponsor.

The world-renowned Street League Skateboarding (SLS) tour made its London debut at the Copper Box Arena last weekend, and a host of top performers were there to compete in front of thousands.

But boarding enthusiasts were outraged to discover the sponsors listed online included Kershaw – who’s tagline is “knives you’re proud to own” and which uses the hashtag #whatareyoucarrying.

Not only is London in the middle of a knife-crime epidemic, the event was also sponsored by Sadiq Khan.

Once it was raised last week the logo was removed. The Mayor’s Office said the company was not a partner and its logo was only used in connection with the event in error. SLS also said the company was “not a sponsor or partner” of the event.

But Kershaw then told skateboarding writer James Davis on Twitter it was still an SLS sponsor. And James said the Kershaw logo was on the website for months.

He told the Gazette: “It’s disgraceful this brand that has been marketing knives to youths is associated with skateboarding in London, a city with a knife crime epidemic. Knives have nothing to do with skateboarding and it would be deeply offensive in any country, let alone here.”

James also scoffed at claims the sponsorship was only listed online in error, saying the only error was that no one had noticed the association.

Skater turned fashion designer Blondey McCoy, also spoke out. He posted on Instagram: “The marketing of knives to teenage skateboarders in the midst of a knife crime epidemic is something quite absurd that we can all live without.”

The Mayor’s Office said: “Kershaw is not a partner of the event in London. The mayor would not support an event in London with Kershaw’s association or involvement. The company’s logo was included by SLS on the event webpage in error.”

SLS did not respond to the Gazette’s request for comment.