On Monday the two other suspects had been brought before a judge and freed on bail, to be tried on 20 and 27 October respectively.

According to public prosecutors in Lisbon all three are suspected of the crime of damage of property. One of the first two to be brought before a judge is also suspected of possessing a prohibited weapon and of physical assault.

Police had detained two men on Monday at a highway roundabout near the airport that taxis had blocked as part of their protest, and a third man near the airport itself. One of the men at the roundabout was said to have been detained for having thrown objects at a police car and the other for hurling a pyrotechnic devise at officers.

The other man, a taxi driver, was detained for vandalising a car used for passenger services with the Uber online platform against whose planned legalisation the protest was called.

Monday's go-slow protest was supposed to have headed for parliament, but instead stopped near the airport, triggering clashes with police. The area was blocked for more than 15 hours.

The protest was called after the government unveiled draft legislation to create a legal framework for the first time for online platforms for passenger services, such as Uber and its Spanish rival Cabify.

Taxi drivers are demanding that the platforms be prevented from operating until the law is approved, and that there be an upper limit on the number of cars that work with them, as there is for taxis.

A fresh protest has been called for Monday in front of parliament and the town halls of Porto and Faro.