One man is fighting for his life in hospital after two people fell from a cliff in Major's Hill Park near Parliament Hill early this morning.

Police say two men jumped a fence and tumbled down a 40-foot cliff near the Rideau Canal and the Ottawa River at about 1:30 a.m. Thursday.

Three females were also present at the time of the incident. However, when one tried to make her way down to help, the other pulled her back up.

A 20-year-old man suffered a severe head injury in the fall and remains in the intensive care unit at the Ottawa Hospital where he's listed in critical condition.

Three others were hurt, including a 36-year-old man who suffered a fractured arm and back pain. A fifth person was unharmed.

Two paramedics who responded to the scene reported being assaulted when they arrived. Police have now charged a woman for allegedly attacking a police officer at the scene.

Although police are investigating, they don't believe foul play was involved.

"It's still under investigation," said Const. J.P. Vincelette.

"What we can confirm is that it appears that alcohol was a factor in this matter and we certainly encourage all members of the public to be very careful when walking in that area."