Seven climate protesters have been arrested after breaking through a perimeter fence and setting up a barricade on an airport's taxi-way.
Flights to and from Aberdeen Airport have been delayed as a result of the security breach by members of the Plane Stupid campaign group.
After talks with police, seven of the protesters gave themselves up six hours after the demonstration began - but two others remain on the roof of the terminal building.
A Grampian Police spokesman said: "We can confirm that following a dialogue between police officers and some of the protesters, seven people have released themselves from their position on the runway and have been taken into police custody.
"Two protesters remain on the airport terminal building roof. Work continues to peacefully resolve the protest."
Plane Stupid said the activists broke through the perimeter fence at about 2am on Tuesday in protest against the airport's expansion plans and the resulting increase in greenhouse gas emissions.
The group added that the activists were dressed as golfers in the style of US property tycoon Donald Trump, who is planning to build a major international golf resort in the area and supports the expansion of the airport.
A spokesman for airport operator BAA said of the protest: "This action is dangerous and highly irresponsible, not least because Aberdeen is one of Europe's busiest commercial heliports and a major transport centre for the north of Scotland, used by tens of thousands of people every day.
"There is no justification for this irresponsible action, which is deliberately calculated to delay and inconvenience the travelling public."
BAA added that flights are leaving but there is likely to be some knock-on disruption and passengers are advised to check the status of their flight early.
A group of climate protesters threatened to disrupt an airport after setting up a barricade on the runway.
Plane Stupid said seven people had broken through the perimeter fence at Aberdeen Airport and placed themselves inside a wire "fortress" on the tarmac. Several other protesters had climbed on to the roof of the terminal building, it added.
The group said the activists invaded the site shortly after 2am and that they were hoping to prevent the airport from reopening later on Tuesday morning.
A spokesman for airport operator BAA said: "Seven people appear to have cut a hole in the security perimeter and are now on the runway. There are two or three on the terminal roof. The police are on their way."
The first flight out of Aberdeen was scheduled to leave at around 6.30am, the BAA spokesman said.
Plane Stupid said it was protesting against the airport's expansion plans and the resulting increase in greenhouse gas emissions.
The group said the activists were dressed as golfers in the style of US property tycoon Donald Trump, who is planning to build a major international golf resort in the area and supports the expansion of the airport.
One of the protesters on the runway, Dan Glass, 25, from Glasgow, said: "There are seven of us here who are fenced in. Two security guards are watching us, and have called for some more people."
He added: "We're here to say the expansion cannot happen, and our generation won't let it happen.
"The scientists tell us we've got seven years to make emissions peak then drop, and if we fail, the people on this runway and their entire generation, and our children, will live with the consequences. That's why we're doing this."