JANESVILLE, Wis. -- There are some new visitors in Janesville these days and they are coming to town via the rain-swollen Rock River, but they aren’t exactly invited guests.

VIDEO: Watch The Report | SLIDESHOW: View Images Of Fish Swimming In Flooded Janesville Streets

The Rock River has risen above containment walls in the city's downtown and the floodwaters are bringing along hundreds of fish.

The north end of Main Street is underwater and the fish have been spotted swimming in the streets and attracted many spectators, WISC-TV reported.

Locals are calling the fish "Rock River salmon” because the larger ones try to swim upstream in the United Way parking lot, but they're actually carp. The carp are using the calmer waters inside a walkway railing as a resting place, capturing the curiosity of passersby.

The state Department of Natural Resources officials said that the fish will take advantage of the floodwaters when it comes time to reproduce and that could be what the carp are doing right now.

"We're looking at big hatches in a lot of our game fish in the Rock River -- the walleyes, the northern pike,” said Don Bush, the DNR fisheries supervisor for the Lower Rock River Basin. “The downside of that is, this time of year, the carp are spawning, and we might see a big hatch of carp as well."

The presence of the fish could be a problem if water recedes too quickly and they're stuck outside the river.

However, the biggest danger associated with Janesville’s new occupants is that the fish are attracting people to the river.

The Rock Sheriff's Department, along with the DNR, is reminding onlookers that it's dangerous to be near the floodwater as it might contain sewage and other chemicals. They're reminding the public to stay away.

Stay tuned to WISC-TV and Channel 3000 for continuing coverage.