More than 400 people, mostly children, were detained in France after high school students across the country protested over class sizes, teacher shortages, and long school days.

The Education Ministry said about 400 schools were affected, while clashes between protesters and police occurred in several cities.

Police reported that 48 officers were injured, with some protesters accused of throwing objects and hydrochloric acid and damaging property.

The demonstrations have drawn support from some local officials and left-wing politicians, while the government has called for calm and criticized what it described as violent escalation, The Guardian has reported.

The protests are also occurring alongside nationwide union strikes over the government’s budget plans, which include €54 million in public spending cuts.