A Regina restaurant has voluntarily closed its doors following concerns about people who have tested positive for E. coli, a digestive tract ailment often linked to meat products.

According to local health official Tania Diener, five cases of E. coli — confirmed in people from Regina and others who were visiting Regina — had one thing in common: they had all eaten at the restaurant Flip in the last week.

Diener noted, however, that the restaurant is inspected regularly and was recently re-inspected, and there are no issues to report.

Nevertheless, the owner of the restaurant — Timothy Martin — said he decided to close the doors.

He said the restaurant is working with health inspectors to determine the source of the E. coli cases.

"We really don't know right now," Martin said. "We're in the middle of the investigation."

He said the decision to close, temporarily, was based on concern for safety.

"We made our decision to ... keep safety at the forefront," he said. "That's our biggest concern."

Earlier on Tuesday, provincial health officials said a total of 13 E. coli cases, across Saskatchewan, had been confirmed in recent weeks.

With files from CBC's Lachlan Madill