Traffic jams clogged the streets of Lisbon on Tuesday as the latest strike over austerity in the bailed-out country halted the city's metro system.
"The workers are fighting because they have to. The government is stealing from us with these austerity measures," said Anabela Carvalheira, an official with Portugal's FECTRANS transport and communications union.
It marked the latest union dispute with Portugal's cash-strapped government over pay and conditions, and further strikes are expected on October 15 unless agreements can be reached.
Despite the deployment of rail replacement buses, the grounding of the metro used daily by some 500,000 people led to long lines of vehicles in the capital's streets.
Service was suspended on Monday night at 11:00 pm (2230 GMT) and was not due to reopen until 6:30 am on Wednesday, a statement from the Lisbon metro said.
Portugal received a 78-billion-euro ($106 billion) bailout in May 2011 from the EU and International Monetary Fund which lasts until June 2014.
In exchange for the lifeline, Portugal's government has imposed tax increases and wage cuts for public workers in a bid to balance the budget, aggravating a downturn that has sent unemployment to a record 17.7 percent.