The appeal for information to find Gianni Sonvico has taken to Twitter. Gianni's sister, Maya, has promoted the hashtag #findgianni as a way of making more people aware.
The sister of missing barrister Gianni Sonvico has made a video plea on YouTube. In the video Maya Sonvico asked anyone with information about her brother's whereabouts to come forward. You can watch the video by clicking here.
Police are searching for a man, believed to be originally from Pembrokeshire, who's been missing in London since Friday.
They say the disappearance of 23 year-old Gianni Sonvico is "completely out of character".
He was last seen at an Underground station.