MANTECA (CBS13) – A playground at a Manteca school used by special needs children was set on fire.

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Fire investigators say the school was locked up and that the arsonist had to jump the fence in order to get to the playground.

Fire crews captured photos of the smoke billowing high in the sky. And once they arrived, fire crews say flames had already engulfed the entire playground at John McFall School Monday evening.

“It was just really loud — lots of smoke — there’s sirens and it looks pretty sad,” said neighbor Ryan Steele.

The Manteca Fire Department says someone intentionally set the fire to the structure used by special needs children.

“It pretty much melted it. It’s all rubber and plastics. There was little evidence left,” said Manteca Fire Department Battalion Chief David Marques.

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Investigators aren’t sure where exactly the fire started, but it’s the second time in recent memory they’ve responded to a playground fire at the school. Last year, someone attempted to burn down this play area. Fortunately crews put that blaze out before it caused significant damage.

“It’s just horrible. It’s just really, really. I mean, that’s the bottom thing you could do is try to attack the special needs kids,” said Rene Torrey, a neighbor.

Now investigators are looking into whether these two cases are connected, and if the same person could be behind other arsons throughout the city, including several vans that were set on fire at East Union High School.

“It’s just cruel,” said Steele.

As investigators look into all leads, neighbors remain hopeful firefighters will catch the arsonist before he — or she — strikes another match.

The playground was worth about $60,000, which was paid for using grant money. It’s unclear whether they’ll be able to rebuild.

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The fire was contained to just the playground. No one was hurt.