Comedian Joan Rivers is reported to be in a "critical condition" after being rushed to a New York hospital

A spokesman for the New York Police Department said: "An 81-year-old is in a critical condition at Mount Sinai Hospital."

He was unable to confirm reports on the TMZ website that her heart had stopped beating at one point.

The US site is reporting that Rivers was undergoing a throat procedure in a clinic when she became unwell but the spokesman could not confirm this.

He said the emergency call was made at 9.39am local time from an address in East 93rd Street, Yorkville, where there is an outpatient centre which describes its mission as to "serve as a community resource for digestive disorders".