DENVER — The problems on the 16th Street Mall are having a major negative impact on Denver tourism and convention business, a study shows.

Visit Denver, a destination marketing organization, issued the report seven months ago, using data from 2014.

It blames problems on the 16th Street Mall for driving away convention business.

Natahsa Maraj from the United Kingdom was in Denver for a convention.

“The impression for me wasn’t that great and I didn’t realize Denver was, um, in need,” Maraj said. “It was quite shocking. I know in London we have homeless. There’s areas in every part of the world that require some attention but to see this out here, I was quite amazed.”

The report presented to mayor and city council concluded:

“The downtown environment is the No. 1 complaint from meeting planners. … The severity of this issue has increased and as of 2014 nearly 50 percent of meeting planners negatively commented on homeless, youth, panhandling, safety, cleanliness, and drugs, including public marijuana consumption.”

In June, a video of a man attacking people on the 16th Street Mall with a plastic PVC-type pipe went viral.

The violent attack happened two days after police and city leaders vowed to crack down on unruly visitors to the popular pedestrian mall.

Metro State University marketing professor Darrin Duber-Smith said the issues are tarnishing Denver’s world image.

“I think the city’s just hoping this is going to go away,” Duber-Smith said. “When you’ve got folks who are attending conventions who aren’t happy with the environment it becomes a problem.”

In fact, several convention organizers are quoted in the report as saying that’s the main reason they won’t be returning to Denver.

However, the mayor’s office said increased police presence on the mall is already making a difference and they’re hearing that from the public.

Visit Denver said it commends the city’s efforts to address the issues head-on.