A police department in the US state of California has apologised, after its coroner's office mistakingly identifying the wrong person as dead.

The Orange County Sheriff's Department says it is conducting an internal review over the incident.

Reports say the family of 57-year-old Frank M Kerrigan was informed that his body was found behind a phone shop in May.

His family held a funeral and buried the still-unidentified body, according to the Orange County Register.

However this was thrown into doubt when Mr Kerrigan showed up at the home of a long-time family friend, 11 days later.

Bill Shinker then called Mr Kerrigan's father, also named Frank, to tell him the news.

"Bill put my son on the phone", Mr Kerrigan recalled to the newspaper. "He said 'Hi Dad'."

Frank Kerrigan holds onto a a funeral card for his son Frank. Kerrigan thought his son had died and later learned he buried the wrong man | Image: Andrew Foulk/AP/Press Association Images

It is believed the incident was part of a mix-up that involved a man found dead, a lack of fingerprint records and a mistaken photo identification.

In a statement, the Orange County Sheriff's Department says: "The department extends regrets to the family of Frank M. Kerrigan, 57, for any emotional stress caused as a result of this unfortunate incident.

"As part of the internal investigation, this incident and all identification policies and procedures will be reviewed to ensure no future misidentifications occur".

#OCSDPIO: @OCSD Investigating misidentification by OC Coroner Office pic.twitter.com/SwtQfQXf8r

— OC Sheriff, CA (@OCSD) June 24, 2017