And now riders are calling for the trains to be cleaned up.

“They need to do something,” said a rider who works in downtown Minneapolis and asked not to be identified.

“I really think there should be someone there monitoring it, at least in the morning,” she said.

More from KSTP

A Metro Transit spokesperson said they are adding four staff members to the Target Field Station to help clean the trains during the day.

They are also considering closing the Green Line from 2 a.m. to 4 a.m. during the week for maintenance and cleaning, which is already done for the Blue Line.

“Obviously hygiene on the trains has become an issue,” said Lt. Mario Ruberto with the Metro Transit Police.

He spoke to the Metropolitan Council Committee of the Whole Wednesday. He said he’s also concerned about the safety of those whose only option is to ride the train all night.

“I think it's important to recognize that people who are homeless on the system need our help,” Ruberto said.

On any given night, he said there’s an average of 200 to 300 people using the transit system as a shelter.

According to Ruberto, many face barriers securing housing because they have mental health issues, a poor housing history or a criminal background.

“If people have nowhere to go, they end up on the transit system,” he said. “The people who end up on the trains and buses really deserve better than that.

"They deserve a place that has a bathroom and a kitchen and food.”

His Homeless Action Team has been working overnights since September, connecting those individuals with services. From November through April, they used two donated Metro Mobility buses to bring people to a Ramsey County shelter in St. Paul.

“We move people - sometimes 30 to 40 to 50 people a night - from the light rail trains and the transit system to the winter safe space,” he said.

They also work with the individuals to put them on a path toward stable housing.

They've been able to get 10 families housed and another 36 in the process by working with the Council's Housing and Redevelopment Authority (HRA).

That came through the 89 new federal housing vouchers HRA secured for people who are homeless, not elderly and have a disability.

Ruberto said they will continue to work with state and local partners to find a solution to homelessness.

“There’s no one magic bullet on this one,” Ruberto said.

“We have to look at it from many different angles and just continue to work at it. The answer is never going to be zero. There will never be zero homelessness. So we have to manage our expectations there, but I think we can do a heck a lot of better than we have been doing.”

Ruberto said they are also getting ready to launch a pilot program to figure out who is using the transit system and emergency services most frequently.

They want to identify the top 30 people so they can focus services on them.