CLEVELAND (WJW) — Officials in Ohio have opened an investigation to determine what happened when an ambulance crew in Cleveland was listed on one call for four hours.

The incident happened last month during the NFL Draft weekend and on a day when the city was short on ambulances to answer residents’ calls. NewsNation affiliate WJW reports that the investigation is looking into whether an emergency medical services crew was forgotten or whether dispatch somehow lost track of that unit.

A dispatch record shows that May 1, an EMS unit was sent on a medical emergency at 2:03 p.m., but the call wasn’t closed or marked complete until 6:21 p.m. The record also shows the patient refused to go to a hospital.

So, how is an ambulance crew lost in the system for hours?

A statement from Cleveland City Hall said, in part, “This incident is being investigated by the Office of Integrity Control, Compliance, and Employee Accountability.”

Cleveland City Hall is not answering follow-up questions since there’s an internal investigation, WJW reports. The EMS union also said it is not answering questions for the same reason. However, the union president did point out that the crew members said they followed proper procedure.

WJW has repeatedly investigated delays and short-staffing with Cleveland EMS exposing a chronic problem.

Cleveland City Councilman Michael Polensek has been watching issues with your ambulance service closely.

“I would tell you, that’s unacceptable,” Polensek said. “Also, there are supervisors allegedly out in the field. So, again, for a unit to be out of service for four hours at a location they responded to would have raised questions with me. Was the crew alright?”

WJW went to the address of that call and also didn’t get any answers there.

As for staffing on that day, records show the city was short six ambulances that afternoon, meaning EMS operated at about a quarter below its normal staffing.