The search for Jon Jonsson in a north Dublin Park will enter its third day today.
The missing Icelandic man was last seen five-years-ago, in February 2019, after he left the Bonnington Hotel in Whitehall.
Mr Jonsson was in Dublin for a poker tournament and planned on staying for a holiday afterwards.
A search started on Tuesday with members of the Garda water unit and cadaver dogs brought in to Santry Demesne Park, near where he was last seen.
On day two of the search, the cadaver dogs picked up something; it is still too early to indicate what they found but it does warrant further investigation.
The area has been sealed off and the Garda Technical team will carry out a forensic examination.
Anonymous tip offs
Since February 2019, Gardaí have established 270 lines of inquiry but this week’s search was prompted by the arrival of two anonymous tip offs.
Gardaí have urged the sender or senders of the information to get in touch with them.