Updated

Egypt's national air carrier grounded its international flights from Cairo Friday because of a 12-hour strike by the company's flight attendants.

Hundreds of passengers crowded into the airport, some protesting the disruption of their travel plans and arguing with airport staff. Security checkpoints were set up on the road to the airport to keep passengers away, preventing a bigger backlog because of the strike that began after dawn Friday.

Some passengers dodged the roadblocks, carrying their luggage and walking to the terminal.

Company officials said as many as 20 international flights were cancelled, but domestic flights were not affected. EgyptAir estimated its losses from the canceled flights by midday at $10 million.

The flight attendants are demanding improved working conditions.

Tamer el-Sioufi, a spokesman for the flight attendants, said the attendants have been conducting negotiations with company officials, but without results.

"We have informed civil aviation officials of the strike time after they procrastinated in meeting our legitimate demands for 16 years," he said. "We will continue our strike (actions) until our demands are met."

The flight attendants' walkout was due to end at 4 p.m. local time.

EgyptAir cabin crew employees have long complained of shortage of staff, accusing the company of using the minimum number of attendants, undermining services. The attendants are calling on management to establish a separate unit in the company for the cabin crews, along with an increase in their benefits.

Roushdy Zakaria, chairman of the board of EgyptAir, told a local radio station that the company is unable to meet the financial demands of the attendants because the airline has absorbed "major losses" since the uprising that toppled longtime President Hosni Mubarak last year. In the wake of the turmoil, tourism to Egypt has dropped considerably, cutting into EgyptAir's passenger volume.

Another official, Mohammed Manar, adviser to the civil aviation minister, said the attendants went ahead with their strike, surprising the company management after an agreement on most of their demands, because the company was unable to increase their wages. A statement from EgyptAir promised wage hikes in mid-2013, the start of the fiscal year.

Zakaria said if the financial demands of the attendants are met, that would prompt other employees of the company to demand similar treatment, straining the budget of the 80-year-old flagship airline.

Last October, air traffic controllers staged a work stoppage to demand better work conditions, causing delays of scores of flights and leaving passengers stranded for hours at Cairo's airport.

Labor unrest has become common in Egypt since the popular uprising last year. Labor unions complain of rampant corruption and outdated laws, demanding the replacing of officials and restructuring of state-run companies.

Manar said EgyptAir has hired cabin crews from private companies to get some flights out. Flights to Saudi Arabia and Kuwait were able to leave Cairo airport.