DENVER -- By day, people are enjoying lunch at Civic Center Park. But at night, the rats take over.

"I seen them right there," said one man as he pointed to an area where he's spotted the rodents before.

The Denver Department of Public Health and Environment (DDPHE) is monitoring the issue and taking steps to combat the problem.

"We have seen an uptick in the number of complaints and referrals related to this issue," said Danica Lee, Public Health Inspections Director for the City of Denver.

Lee said rats can be found in any urban environment, but due to the recent complains the city is taking action.

“We try to eliminate the food that they may have and also eliminate any areas where they may make their nests," said Lee.

She adds that residents and visitors to the park can also help by picking up after themselves. The stretch of grass leading up to the State Capitol is often times littered with trash and Denver7 crews found garbage near the Colorado Veteran's Monument despite the trash cans nearby.

The Denver Department of Parks and Recreation is trying to empty trash cans more often and is working with an exterminator.