A child and a man have died in separate incidents on Christmas day

A two-year-old boy has died after he was thrown from a quad bike and a man has drowned in two tragic Christmas Day incidents in Victoria.

The toddler, who was the passenger, was trapped underneath the vehicle before witnesses freed him and performed CPR. Sadly, he could not be saved.

Police said the incident happened at private property on Moss Road in Barnawartha North, in Victoria's north-east, 11.50am today.

The driver of the vehicle is assisting police with their inquiries and the cause of the crash is being investigated.

Meanwhile, police said two men were swimming with friends at Squeaky Beach at Wilson's Promontory when they got into difficulty about 3.40pm today.

A member of the public managed to pull one of the men from the water.

CPR was commenced however he died at the scene.

The second swimmer is yet to be located and a search is under way including local police officers and the Air Wing.