A 24-hour strike by Lisbon subway staff has snarled rush-hour traffic in the Portuguese capital in the latest protest against the bailed-out country's austerity policies.

The Metropolitano de Lisboa carries on average a half-million passengers a day.

Unions representing subway workers called the walkout Thursday over labor reforms and cuts in entitlements. The government is enacting those measures in return for a 78 billion euros ($101 billion) financial rescue two years ago.

The protest comes ahead of a spate of strikes by government workers and employees of public companies in coming weeks, including a planned walkout by teachers during the period of high-school summer exams.

The country's two trade union confederations, representing more than 1 million mostly blue-collar workers, are also considering rare joint protests.