The Lerwick Coastguard attended two different call-outs on Saturday afternoon.
In the first, a person described as potentially “vulnerable” went missing in the north end of Lerwick after becoming seperated from friends and family on a walk.
The Coastguard assisted Lerwick police officers in locating this person, who was discovered safe and well.
They then attended a 999 call from a concerned member of the public about a rubber dinghy which had allegedly capsized, with three people going into the sea in “the Breiwick bay area” of the town, a Coastguard spokesman said.
The Lerwick Coastguard put out a mayday call for assistance from other vessels in their search, but the crew was stood down with nothing found.