More than 1 million people have taken part in demonstrations across France as transport, schools, and refineries were hit by strikes in protest at Emmanuel Macron’s unpopular plans to raise the retirement age by two years to 64.

Iran PressEurope: France interior ministry said 1.12 million people protested nationwide on Thursday, with 80,000 taking part in the biggest rally in Paris. Trade unions said the figure was even higher.

Police made arrests on the edges of the march in central Paris amid clashes with officers in the early afternoon. Police said 15 people were arrested before the Paris march and 15 during it, for offenses such as carrying illegal weapons or throwing projectiles. Shopkeepers around the Place de la République boarded up windows and shopfronts after the authorities warned of a possibility of vandalism after the marches or black bloc-style tactics.

Local and regional train services across France ground almost to a standstill, and public transport in cities including Paris was “very disrupted”, according to operators.

Many primary schools closed for the day. Authorities estimated 40% of primary teachers and more than 30% of secondary teachers went on strike. Unions said participation was higher, at 70% in primary schools.

Public service radio and television were also disrupted, and some theatres and museums closed. Some refinery shipments were blocked and energy output lowered.

The 24-hour strike and protests in 200 towns and cities are the first big test for Macron since his re-election against his far-right rival Marine Le Pen last spring.

Macron has made the pensions issue a marker of his aim to transform France and overhaul its social model and welfare system. He insists he will deliver his key election pledge to change the French pension system – raising the retirement age for most people to 64 from 62 and increasing the years of contributions required for a full pension.

Opinion polls have shown most French people oppose these proposals and view them as unjust, even if many agree with a need for change.