A woman has been shot dead in clashes between security forces and protesters in Panama.
She was the third person to be killed in protests over legislation allowing the sale of land in the duty-free zone of Colon, local media report.
The protesters fear the new laws, which were passed on Friday, will cost jobs and cut incomes.
But President Ricardo Martinelli says the sale of the state-owned land will benefit the region.
The death of the 27-year-old woman follows that of a man and a nine-year-old boy in clashes over the past five days.
President of the Colon Chamber of Commerce Anacleto Ceballos announced on Tuesday that a 48-hour strike would be extended for another day.
A government delegation which had travelled to Colon to meet the protesters returned to the capital, Panama City, on Tuesday after the activists refused to talk to them.
The protesters had demanded that the new legislation be repealed before they enter into talks with the government.
The demonstrators, which include trade unions, members of the Colon Chamber of Commerce and a variety of civil society groups, want the land sale scrapped.
They demand that the government instead raise commercial rents in the duty-free zone and that the resulting money is invested in Colon, which has a high crime and poverty rate.
Economy Minister Frank De Lima said the government remained open to dialogue. "I'm optimistic that we'll come to an agreement in the best interest of Colon," he said.
Mr De Lima said he was in close contact with President Martinelli, who "was following events in Colon closely".
President Martinelli has come under criticism for not breaking off his trip to Asia in the face of the continuing protests.
The city of Colon has one of the largest free trade ports in the world, in operation since the 1950s.
It sits at the end of the Panama Canal and just outside the former Panama Canal Zone.
The canal, linking the Atlantic Ocean to the Pacific, is Panama's main source of revenue.