According to a statement of the spokesman for the secretary-general, Guterres extended his deepest condolences to the families of the victims.
He also expressed his solidarity with the government and people of Turkey and of those countries whose nationals were impacted.
Guterres expressed the hope that the organizers and perpetrators of this "heinous act" would be identified and brought to justice swiftly, says the statement.
A gunman stormed into Reina nightclub early Sunday morning and shot at hundreds of people gathering there for New Year celebrations, leaving at least 39 killed and over 60 others injured.
XINHUA/MNA