Police Scotland are continuing to investigate the sighting of a man who entered the River Clyde near Glasgow Bridge on Tuesday May 11.
The extensive search to find the unidentified man last seen around 2:30pm is also being assisted by a police helicopter.
Dive and marine teams, the Humane Society and SFRS have all also been involved in the ongoing rescue efforts.
They arrived at the area surrounding the bridge, near Jamaica Street in the city centre on Tuesday afternoon after receiving reports of a man in the water.
The family of Brian Hamill, a missing man from the Partick area of Glasgow have been made aware of the incident.
Brian, 39, was last seen at his home address in the Dumbarton Road area at around 2:10am on Monday May 10.
He is described as white, 5ft 10ins tall, of a medium build with short fair coloured hair.
It is not known what he was wearing the day that he went missing.
Inspector Katrina McLaren said: "Along with his family, we are becoming increasingly concerned for Brian’s welfare and we are keen to find him as soon as possible.
"I would urge anyone who may have seen Brian to contact us.
"Similarly, Brian if you are reading this, let us know that you are safe and well."
Anyone with any information should contact Police Scotland on 101, quoting incident 1746 of 11 May.
