California authorities are searching for a man with ties to European royalty who disappeared in Malibu early Saturday morning.

Attilio Brillembourg, 53, was last seen at 1:10 a.m. in the 6000 block of Murphy Way, a neighborhood of luxury homes and estates near Escondido Falls, according to the Los Angeles County Sheriff’s Department.

“There is concern for Mr. Brillembourg’s well-being,” the department said in its missing person report.

According to the Daily Beast, Brillembourg’s father, who shares the same name, is the stepfather of Princess Tatiana of Greece and Denmark. Tatiana was married to Prince Nikolaos for 13 years before the couple announced their separation last month.

Tatiana, 43, whose surname is Blatnik, retained her royal title, PEOPLE reported.

Nikolaos is the third child of the last king and queen of Greece before the monarchy was abolished in 1973.

The sheriff’s department says the younger Brillembourg no longer has ties to the family.

Brillembourg is 5 feet, 10 inches tall and weighs 165 pounds. He was last seen wearing a blue shirt and gray pants and no shoes, authorities said. Anyone with information was asked to contact LASD’s Homicide Bureau at 323-890-5500.

NewsNation affiliate KTLA has attempted to contact Princess Tatiana but has not received a response.