A wall in the parking area for staff at San Anton Palace collapsed early this morning.
The wall, which was being restored, collapsed at 2.45am. A number of cars were damaged.
Magistrate Simone Grech is leading an inquiry into the wall's collapse.
In a statement, the government said nobody was injured when the boundary wall in the main courtyard of San Anton Palace collapsed.
The San Anton public gardens are closed as a safety precaution and an inquiry is underway to establish the cause.
The Restorations Directorate is looking into the technical side of the matter.
San Anton Palace has been the official residence of the President of Malta since 1974. It was originally built in the early 17th century as a country villa for Antoine de Paule, a knight of the Order of St John.
The palace is surrounded by the extensive San Anton Gardens, parts of which have been open to the public since 1882.