TAMPA, Fla. (CNN) - Citing poor economic conditions, US Airways Group Inc. Tuesday told mechanics at its Tampa maintenance hangar the facility was being shut down and up to 300 of them may be losing their jobs, mechanics said.

"We just gave all these [wage] concessions and now we're going to be shut out," said a mechanic at US Airways for 12 years.

The mechanic asked that his name not be used.

According to the mechanic, nightshift mechanics arrived at 11 p.m. By 4 a.m., they had been given paperwork saying the airline was closing the Tampa hangar. Employees have until Friday to remove their tools and other personal belongings from the facility.

The airline, the nation's No. 7 air carrier, has been operating under bankruptcy court protections and has won new labor agreements from its unions aimed at cutting costs. It operates three other maintenance hangars around the country, the mechanic said.

Information about employee transfers or severance pay were not immediately available.

US Airways could not immediately be reached for comment.