At least five people were arrested after Saturday's attack on the office in Moron, 500 kilometers east of Havana.
"What began peacefully degenerated into vandalism after clashes with authorities," said the newspaper Invasor in a brief notice.
Protests are often ignored by state-controlled media.
But growing protests, caused by sharply deteriorating living conditions, prompted President Miguel Díaz-Canel to make a highly unusual statement:
"I can understand the dissatisfaction our people feel due to prolonged power outages," he wrote on X, but warned of consequences for those who resort to violence.
