LONDON (AP) — Tens of thousands of railway workers walked off the job in Britain on Tuesday, bringing the train network to a crawl in the country’s biggest transit strike for three decades.

About 40,000 cleaners, signalers, maintenance workers and station staff held a 24-hour strike, with two more planned for Thursday and Saturday. Compounding the pain for commuters, London Underground subway services were also hit by a walkout on Tuesday.

The dispute centers on pay, working conditions and job security as Britain’s railways struggle to adapt to travel and commuting habits changed — perhaps forever — by the coronavirus pandemic. With passenger numbers still not up to pre-pandemic levels and the government ending emergency support that kept the railways afloat during the past two years, train companies are seeking to cut costs and staffing.

Unions say it could be the start of a summer of labour discontent as British workers face the worst cost-of-living squeeze in more than a generation. Lawyers in England and Wales have announced they will walk out starting next week, and teachers’ unions plan to consult their members about possible action.

Major railway stations were largely deserted, with only about 20 percent of passenger trains scheduled to run on Tuesday.

With inflation currently running at 9 percent, the Rail, Maritime and Transport Union says it cannot accept rail firms’ latest offer of a 3 percent raise.

But the train companies argue they can’t offer more, given current passenger numbers. There were almost 1 billion train journeys in the UK in the year to March — compared to 1.7 billion in the 12 months before the pandemic.

While the Conservative government says it’s not involved in the talks, the union notes that it plays a major role in the heavily regulated industry, including providing subsidies long before the pandemic, and argues it could give rail companies more flexibility to offer a substantial pay increase.

The government has warned that big raises will spark a wage-price spiral driving inflation even higher.

Millions of people in Britain, like those across Europe, are seeing their cost of living soar, in part driven by Russia’s war in Ukraine that is squeezing supplies of energy and food staples, including wheat. Prices were already rising before the war, as the global economic recovery from the COVID-19 pandemic fueled strong consumer demand.