Image copyright Beds Police Image caption Michael Grimes pleaded guilty to 17 counts of child sexual abuse over a 40-year period

A 70-year-old child abuser whose crimes were labelled "vile, despicable, and perverted" has been jailed for more than 20 years.

Michael Grimes, of Croft Green, Dunstable, pleaded guilty to 17 counts of child sexual abuse over a 40-year period.

Luton Crown Court heard his offending including making images of babies being abused.

He will serve 23 years in prison and put on a sexual harm prevention order.

Image copyright Beds Police Image caption Police found a number of recording devices when they raided Grimes' home

His home was raided by police in July 2016 and officers found a number of devices including a miniature covert recording device.

These devices were found to contain more than 4,600 indecent images of children and babies - including almost 1,000 of the most severe category.

Police dealt with four of those abused during their investigation.

Sentencing Grimes, Judge Michael Kay QC said his actions were not only "vile, despicable, and perverted" but went "beyond normal human comprehension".

Image copyright Beds Police Image caption Paul Baddeley, of Bedfordshire Police, said the investigation involved "one of the worst cases of child sexual abuse" he had "ever dealt with"

Paul Baddeley, of Bedfordshire Police, said: "This is one of the worst cases of child sexual abuse that I have ever dealt with.

"Grimes sexually abused four young girls on multiple occasions.

"His abusing then evolved with the digital age with the viewing and creating of horrific indecent images of children and babies."

The NSPCC said: "Grimes' horrific campaign of abuse will have left untold suffering on his victims who have showed tremendous courage in speaking out and helping to put him behind bars."

He admitted 12 counts of inciting a girl under the age of 14 to commit an act of gross indecency, two counts of assaulting a girl under the age of 13 by touching and three counts of making indecent images of children.