Five activists arrested when they climbed on to the roof of Parliament have been released on bail.
The protest lasted for nearly three hours
The campaigners unfurled banners in opposition to the planned expansion of Heathrow Airport during the three hour protest on Wednesday.
Meanwhile Gordon Brown took part in prime minister's questions in the Commons below.
Police said the five were arrested under the Serious and Organised Crime and Police Act and bailed until April.
The three men and two women are thought to have gained access using visitors' passes, and made their way to the roof via a fire escape.
Mr Brown told MPs decisions had to be made "in the chamber of this House and not on the roof of this House".
Protesters from the Plane Stupid group climbed onto the roof at about 0930 GMT.
They were searched by officers at about 1220 GMT and arrested on suspicion on trespass.
The protest coincided with the final day of the government's consultation on the expansion plans - protesters claimed the result had been "fixed".