More than half of Britain’s 900 KFC outlets have been forced to close because of distribution problems that left the company short of chicken.

The difficulties began last week, when the fried-chicken chain switched its delivery contract from South African-owned distribution group Bidvest to DHL, which blamed “operational issues” for the shortages.

A KFC spokesperson said stores will start to reopen as teams “work flat-out all hours to clear the backlog”, although the company is unclear when the supply issue will be resolved.

“Each day, more deliveries are being made. However, we expect the disruption to some restaurants to continue over the remainder of the week, meaning some will be closed and others operating with a reduced menu or shortened hours,” the spokesperson said.

Despite a special website page by KFC that details whether stores are open or closed, some chicken-lovers expressed confusion about the situation, and a few even called the emergency services.

In response, Tower Hamlets Police tweeted: “Please do not contact us about the #KFCCrisis– it is not a police matter if your favorite eatery is not serving the menu that you desire.”

The Metropolitan Police confirmed to the Daily Telegraph that people had been making time-wasting calls about the issue.

Neil Coyle, the member of parliament for Bermondsey, said constituents had asked him when they will next be able to eat the fast food.

He tweeted: “I’ve been contacted by disappointed #KFC customers … today.”

Luke Pollard, the member of parliament for Plymouth Sutton & Devonport, wrote on his Twitter account: “Have had my first person get in touch to ask what’s happening with #KFC... and the answer is, I don’t know (yet).”

John Boulter, DHL’s managing director of retail, said the delivery company regretted the “interruption of supply” and apologized for the “inconvenience and disappointment caused to KFC and their customers”.

“The reasons for this unforeseen interruption of this complex service are being worked on with a goal to return to normal service levels as soon as possible,” he said. “We are committed to step-by-step improvements to allow KFC to reopen its stores over the coming days.”