Two children suffered serious injuries after a large tree fell in a Chelsea park Monday evening.

Emergency crews responded to Washington Park just before 7pm when they received reports that the tree fell on children that were playing in the children's play area of the park.

Witnesses said they heard cracking noises right before the large tree fell right on top of two little boys on Monday.

The kids -- ages 2 and 8 -- are recovering at a Boston hospital. One of them is being treated for a possible fractured skull.

"His skull is cracked and part of his ear is not that good but thank God he started speaking," Evelyn Mancia said.

There is no word on what may have caused the tree to go down. The park has been closed until the other trees can be inspected.