Pakistan’s state-owned airline grounded all flights Friday, stranding thousands of angry passengers as an employee strike stretched into a fourth day without any sign of negotiations.

Pakistani International Airlines is the country’s largest carrier and one of the few airlines that operates a significant number of domestic flights. At least 250 domestic and international flights have been canceled since the strike began Tuesday, PIA spokesman Mashhood Tajwar said.

No PIA flights were in the air Friday in any city, and the carrier also closed its main booking office in the southern city of Karachi, Tajwar said.

Pilots and support staff went on strike Tuesday over a proposal to have the struggling carrier share routes with Turkish Airlines. PIA managers say the route-sharing idea will lessen its financial losses, but strikers fear it will lead to job and pay cuts.

The strike is costing the airline roughly $6 million (500 million Pakistani rupees) a day, Tajwar said. It’s also likely affecting other parts of the country’s already struggling economy, which is being kept afloat by billions in loans from the International Monetary Fund.

In Karachi, thousands of passengers drifted between information desks asking about any flights as the electronic boards showed all PIA flights were canceled. PIA’s information and ticket kiosks were locked down.

On one side of the airport, members of other labour unions were joining in with the rallying pilots and airline employees, who threw rose garlands around the sympathy strikers.

“We are united!” the group shouted.

In the capital, Islamabad, police carefully guarded gates to the airport. Though plenty of would—be passengers stayed away, some showed up in hopes of finding some sort of alternate path to their destination.

In Rauf Ahmad’s case, that’s Italy, where he hopes to spend a second season working in a fruit orchard. After learning his flight had been canceled, the 28-year-old said he was at a loss about what to do next.

“I just came here to see what is happening and nothing is happening, he said. “I don’t know what happens if I don’t get there on time.”

Rukhsar Ahmad, a former government official in Pakistan’s side of the Himalayan region of Kashmir, was hoping to visit his family in Manchester, England, where he lives part-time and owns restaurants.

“It’s a loss of time, and a loss of money and a loss of business,” Ahmad said while pondering if he could get on another carrier.

The strike is already cutting into Pakistan’s economy, said Muzzammil Aslam, a chief economist as JS Global, a Pakistani investment firm. In addition to passengers, perishable air cargo such as flowers and fruits has been left to spoil. He estimated the export losses from the four days so far at around $20 million.

“It’s quite a major dent to the economic activities,” Aslam said.

Abdul Malik, a representative of Pakistan Fruit Exporters Association said they’ve had heavy losses, as they haven’t been able to get produce to markets in Europe and the Middle East. Now they’re worried that international customers will cancel future orders.

PIA bosses say the route-sharing idea could raise money for the struggling carrier, which has been posting multimillion dollar losses for years because of bad management and competition from Gulf airlines. Carriers around the world have increasingly struck route-sharing deals to tap new markets without investing in extra planes and staff.

Management denies that there will be job or salary cuts, but strikers say they don’t trust the promises and continue to be opposed to the deal.

But strike leaders are adamantly opposed to the idea, though management denies they will see job or salary cuts.

Pakistan’s ruling party is trying to shore up the country’s economy, which is wracked by inflation, chronic power shortages and other problems, but it has met resistance from allies and the opposition on pursuing major reforms, including a new sales tax. Subsidizing PIA and other loss making state-run businesses eats up a significant chunk of the government budget each year.

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