Authorities have identified the fourth individual who is accused of walking onto a sensitive hot spring in Yellowstone National Park.

The criminal complaint says Hamish McNab Campbell Cross, who carries a New Zealand passport, was among a group of men seen and photographed walking on the hot spring on May 14.

The men are accused of leaving an established boardwalk and stepping onto a geothermal feature where they snapped selfies and took video of themselves.

Ranger believe they have returned to Canada where some of them have a clothing line that they promote.

The group posted an apology on their social network and offered to donate up to $5,000 to the park.

One of the men reached through email has decline comment on behalf of the group.