3:48 PM PT -- When asked why Efron was taken to the hospital for a minor incident, his rep once again reiterated it was purely a precautionary measure. However, the rep did not say what caused him to be in distress in the pool.

2:38 PM PT -- The rep for Efron did not reply as to how this could be a minor incident when he was taken out of the pool and sent to the hospital.

12:47 PM PT -- Sources with direct knowledge tell TMZ ... Zac was found inside the swimming pool by two people working at the villa who pulled him out of the water.

Zac Efron was taken to a hospital in Spain after an incident in a swimming pool, but he's doing just fine now ... TMZ has learned.

A rep for Efron tells TMZ ... Zac was taken to the hospital as a precautionary measure after what they describe as a "minor swimming incident" at a villa in Ibiza Friday night.

We're told he was released from the hospital this morning, and he's recovering just fine.

Efron's been traipsing around Europe for a while -- with photogs snapping him in Ibiza, St. Tropez, Mykonos and Paris over the last month. He also hit the stage with Martin Garrix earlier this week ... looking full of life with the famed DJ.

Zac's taking a much-needed summer off ... he's coming off his hit role in the film "The Iron Claw" starring Jeremy Allen White and his appearance alongside John Cena in "Ricky Stanicky."

He's got more on the way too ... including a "Three Men and a Baby" reboot that's currently in pre-production.

We've reached out to local authorities ... so far, no word back.