US basketball star Trent Lockett appeared confused after coming across what he thought looked like a Ku Klux Klan gathering in Spain – only to discover it was a religious festival to mark Easter.

The athlete, who is playing his first year for Betis Energia Plus, had been walking through the streets of Seville on the weekend when he stumbled upon dozens of people marching with their faces covered while wearing white robes and pointed hats.

The outfits bear a striking similarity to the ones worn by members of the notorious US white supremacist group, the Ku Klux Klan (KKK).

Lockett, 26, from Minnesota, posted pictures of the festival goers to his followers on social media while expressing surprise.

He wrote alongside one picture: "Not what I'm conditioned to be cool with just walking down the street like this."

Lockett eventually said the parade was not a racist gathering, but a Christian festival marking Easter.

Every year, towns and cities across Spain take part in Semana Santa parades in the run-up to Easter.

Seville, the regional capital of Andalusia, hosts some of the biggest processions, with some participants carrying large wooden crosses or even walking barefoot as a form of penance.

Those wearing the white robe outfits are said to have their faces covered to allow them to repent anonymously for sins they have committed throughout the year.

Lockett wrote alongside another picture posted to his followers: "One of the craziest things I can imagine seeing. Has zero to do with the KKK though. Traditions back to hundreds of years before the KKK even came to be."

"Still shook though."

Suggesting the sight was a little too much, he added: "Regardless of the meaning...still can't rock with this."

Trent Lockett
Trent Lockett, pictured here in the dark blue basketball top Reuters