Sir Mick Jagger’s family is deeply involved in the urgent search for his granddaughter Assisi Jackson’s long-term partner, who has mysteriously disappeared in Cornwall.

Alexander Key, a 37-year-old chef and father of two with Assisi, 33, was last spotted at a pub in Boscastle on Friday afternoon. CCTV footage captured him leaving the establishment.

His disappearance was reported to Devon and Cornwall Police on Saturday evening, sparking a swift public appeal for assistance.

The last CCTV images of Alexander show him alone at around 2:30 PM at the Cobweb Inn in Boscastle. He left the pub approximately an hour later.

The Cobweb Inn shared these images and urged anyone with information to step forward, stating that “his family are so worried.”

This morning, Assisi’s mother, jewellery designer Jade Jagger, 54, took to social media to share the police appeal with her followers, posting images of Alexander.

He is described by police as being of medium build with distinctive bright peroxide blonde hair and is normally seen wearing bright coloured clothing.

In the police images shared by Jade – daughter of the Rolling Stones frontman and his first wife Bianca Jagger – Alexander can be seen wearing a striking orange patterned jacket.

CCTV images show Alexander Key leaving the Cobweb Inn in Boscastle on Friday afternoon

Alexander Key (back) is seen on CCTV at the Cobweb Inn in Boscastle on Friday afternoon

Alexander Key was last seen in Boscastle on Friday, according to Devon and Cornwall Police

Alexander is described as being of medium build with distinctive bright peroxide blonde hair

Police said they were growing increasingly concerned for Alexander’s welfare as searches and enquiries continue in the Boscastle area.

The picturesque coastal village, known for its dramatic harbour and cliff top walks, attracts visitors year-round but can be treacherous, particularly in winter months.

Officers are urging anyone who may have seen Alexander or knows of his whereabouts to contact them immediately on 999, quoting log number 847 of 24/1/26.

Assisi is the eldest grandchild of rock legend Mick, 82, and the daughter of Jade and her former partner, the artist Piers Jackson.

Assisi and Alexander live in Cornwall, where they are raising their two young daughters, Ezra, 11, and Romy, six.

Assisi Jackson with her mother Jade Jackson in London in October 2014

Assisi Jackson (pictured) is the eldest grandchild of rock legend Sir Mick Jagger

Alexander Key has two children with Assisi Jackson (pictured together)

Jade is the daughter of Sir Mick Jagger and his first wife Bianca Jagger (all pictured in 2013)

Jade took to social media to share the police appeal with her Instagram followers

Alexander co-owns The Rocket Store, a popular seafood restaurant in Boscastle, with head chef Freddie Woodruff.

The restaurant is known for using fresh ingredients, including fish caught daily by Alexander’s father and meat from their family farm.

Its interior features a prominent painting of a star constellation by Assisi’s father, Piers.

Jade was pregnant with Assisi’s half-brother, Ray Emmanuel Fillary, at the same time as Assisi was expecting her first child.

Jade gave birth to Ray just weeks after her granddaughter Ezra was born in May 2014, making Jade both a mother and grandmother to babies born within weeks of each other.