Striking union workers clashed with police at Madrid’s Barajas airport yesterday on the first day of a week-long strike over more than 3,800 pending job cuts at Spain’s flagship airline Iberia.

More than 80 Iberia flights were cancelled as workers at the carrier began a series of five-day walkouts that are expected to cost the airline and struggling national economy millions of euros in lost business.

Hundreds of workers flooded into Terminal 4 at Barajas – the biggest airport in Spain – to noisily protest, chanting and whistling, with one group staging a sit-in. About 2,000 people demonstrated outside the terminal.

The police beat some strikers with truncheons to keep them away from the doors of the international airport, Iberia’s Madrid hub, and forcefully threw others out of the terminal. At least five protesters were arrested.

Flights from other airlines were delayed at airports across Spain, including at Madrid and Barcelona, as Iberia baggage handlers, also working for other airlines, joined strikers.

Air stewards and ground staff are holding three five-day strikes this month and next month to protest against management plans to axe jobs and cut salaries at the loss-making airline. Some 10 per cent of long-haul flights and half of domestic flights will be grounded this week.

Labour unions kicked off the strikes with demonstrations in the morning at most Spanish airports, including Barcelona. At an eight-kilometre march around Barajas, protesters blamed British managers at the airline group for job cuts threatened in Spain. Demonstrators waved Spanish flags and banners saying “British go home”.

Iberia, which merged with profitable British Airways in 2011 to form the International Airlines Group (IAG), reported a loss of €262 million in the first nine months of 2012.

The February 18-22 strike coincides with school holidays in Britain and France, Spain’s biggest source of tourists.