Protests continued to grow in the Panamanian port city of Colon on Tuesday, amid growing unease over a controversial draft law allowing the formerly restricted sale of land in a duty free zone.

While peaceful demonstrations took place in the city's main arteries, police and protesters clashed close to the port area as members of the transport union joined the protest.

Police fired tear gas and rubber bullets as they faced demonstrators throwing sticks and stones and setting fire blockades in the city, which hosts Latin America's largest commercial trading area.

There were no reports of detainees or injuries during the unrest on Tuesday.

On Monday, 50 people were detained during demonstrations.

The Panamanian government called for dialogue over the weekend in an attempt to quell tensions after violent protests first broke out on Friday.

They followed the passing of the law in the National Assembly which went on to be sanctioned by President Ricardo Martinelli.

The new bill opens the door to the sale of land belonging to the state.

Various workers and social organisations quickly mobilised demanding the new ruling be appealed, stating that it will take revenues out of the city.

The government estimates that the sale would raise 2 billion US dollars over the next 20 years and points out that 35 percent of the profits will be ring-fenced for social investment projects in the region.