The Prison Service says there has also been a disturbance at Rye Hill Prison, near Rugby in Warwickshire, but it was unrelated to the Maidstone Prison incident.
"There was a passive demonstration at HMP Rye Hill where around 60 offenders refused to return to their cells," she said.
"This was peacefully resolved within a few hours."
More top news
Nicola Sturgeon will hold talks with European Parliament president Martin Schulz in Brussels today.
IKEA is recalling almost 36 million chests and dressers in the US and Canada after the deaths of three children.
Toyota is recalling 1.43 million cars for an airbag inflator defect.