An unprecedented volume of calls are being received by West Yorkshire Police, the force said, with the recent warm weather thought to be a contributory factor.
During this week the force has handled almost 5,000 calls every day, of which about a third have been emergency 999 calls.
Assistant Chief Constable Mark Milsom said the force was taking longer to answer non-emergency calls as a result.
He said: “This week’s warm weather has led to a high demand in calls and has placed increased pressure on our services. Staff are doing everything they can to answer the telephones and attend incidents.
“We are running with a number of critical incidents and events, as well as looking for 51 people who are missing from home.
“We are therefore prioritising calls where safety is at risk such as emergency calls and missing persons. In spite of the higher than average numbers of calls, our operators are still answering 999 calls in an average of five seconds.
“Due to this prioritising, unfortunately other services such as 101 calls have taken us longer than normal to respond to. We will be working hard over the next few days to clear any blockages and apologise to those affected.
“There are alternative ways of getting in touch including online crime reporting and our webchat facility which can be found on the Force website.
“We would stress though that these online alternatives should only be used for non-emergency incidents and crimes. 999 should still always be used in an emergency or when a crime is in progress, but please think before you contact us for non-emergency issue and ask “is this a Police matter?”