Workers at Los Angeles International Airport went on a one-day general strike today, May 1, to protest what labor activists are calling unfair practices by airlines using hired contractors instead of unionized employees.

The strike went into effect at 3 a.m. and was scheduled to continue throughout the day, according to Martin Terrones, a spokesman for Service Employees Union International-United Service Workers West. Supporting the workers’ May Day strike were Los Angeles labor unions, community groups and religious leaders, he said in a statement.

At noon, hundreds of janitors and other workers from United Service Workers West were to march through several LAX terminals toward Century Boulevard and Avion Drive, were 18 workers and their supporters from community and religious groups planned to hold a civil disobedience action, he said.

Unions say airlines increasingly use non-union contractors to provide key services such as cabin cleaning, baggage handling, wheelchair assistance and ramp and cargo work. The SEIU contends that the use of contracted workers often results in substandard services, dangerous working conditions and employees working for less than living wages and receiving no health care benefits.

Los Angeles World Airports, the L.A. city agency that operates LAX, did not immediately comment on the strike plans or the expected impact on airport operations.

The job action at LAX coincides with heightened security for the one-year anniversary of the death of Osama Bin Laden.