Honda have announced that it was an oil leak that curtailed Fernando Alonso's running in Friday's first practice in Spain.
The double World Champ spun on his out-lap at the Circuit de Catalunya when his wheels locked up as the engine failed.
A notably frustrated Alonso spent a few moments looking at the rear of his MCL32, which had fluid pouring from it.
Honda have confirmed that it was an oil leak.
"[It was an] oil leak on Fernando's car," said a Honda spokesperson.
"The issue is under investigation.
"In the interest of time we are changing the power unit.
"He will be back out on track during FP2. ESS [Energy Store] and CE [Control Electronics] will remain unchanged."
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