A group of pilots and support staff for Pakistan International Airlines are unhappy about a proposed route-sharing deal with Turkish Airlines and have been striking for two days. In Karachi on Tuesday, some employees scuffled with colleagues who opposed the strike.

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.

But some of the airline’s 20,000 employees fear it will lead to job or pay cuts, though management denies this.

PIA spokesman Mashhood Tajwar says the strikers Wednesday are mainly confined to Islamabad, where both domestic and international flights are on hold. Flights have resumed in Karachi, but the 10 aircraft out of use in Islamabad represent a quarter of the carrier’s passenger planes, he said.

“We are deeply concerned because of this situation and we are doing whatever is possible to resolve the issue,” he said.

Carriers around the world have increasingly struck route-sharing deals to tap new markets without investing in extra planes and staff.

The Pakistani government is struggling to shore up the country’s economy, which is already subsisting on billions in loans from the International Monetary Fund. Subsidizing PIA and other loss making state-run businesses eats up a significant chunk of the government budget each year.