One of Liverpool's historic tall ships has sunk in the city's Albert Dock.
Emergency services were called to the Zebu's mooring outside the Tate gallery at about 04:30 BST.
The boat sailed 69,000 miles and visited 41 countries for a youth development project, Operation Raleigh, in 1984.
It also featured on the BBC's Who Do You Think You Are programme in 2008, when interior designer Laurence Llewelyn-Bowen sailed on the vessel.
Albert Dock bosses said an investigation into the sinking had started.
Fire crews used special thermal cameras and lighting to search the water and check for people. No-one was hurt.
Formerly a Baltic timber trader for 30 years, the Zebu was built in 1938 and was later re-rigged as a Victorian-style Brigantine ship. It has been based at the Albert Dock since 1988.
The square rigger vessel is owned by the Mersey Heritage Trust.
A marine surveyor and a team of engineers are on site and it is hoped the vessel will be raised once safety inspections have taken place.