A 10-year-old boy and a 40-year-old woman are recovering from minor injuries after a giant oak tree collapsed on a High Park playground Tuesday afternoon.

Witnesses say about 100 children were playing around the site when the 18-metre tree crushed the playground around 3:40 p.m.

The boy suffered minor injuries, while the woman suffered a broken arm.

Daniel Chirlitti, who was at the scene, says the castle portion of the playground absorbed the tree's impact.

"The break of the tree was saved by the castle itself," says Chirlitti.

The city says the tree was decaying from the inside and there were no external signs of rotting.

Kevin Bowser, the city's manager of parks, says it will take two to three days to make a plan for rebuilding the park. There is no estimate yet for the damge.

The city also says this summer's above average rainfall may have weakened the tree.

City officials also say they survey trees from time-to time to make sure parks are safe, but there was no idea to tell this tree was rotting from the inside.