Two protesters were arrested after stripping off naked to have sex in front of the alter in the middle of a service at Oslo Cathedral.Police arrived to seize the pair - members of the F*** for Forests group - after one shocked churchgoer dialed 999.Other furious parishioners pulled the couple apart and held them until police arrived, and also grabbed a man that had been taking pictures of the act.A police spokesman confirmed: "We arrested three people for sexual activity in front of the altar in Oslo Cathedral."A spokesman for the trio - who have not been identified by police - said: "We had to pay a small fine or spend 16 days in jail. We chose the former because we didn't want to spend so long without having sex."Swedish pressure group F*** For Forests is trying to publicise global deforestation by having sex in public to draw attention to the problem.It believes in campaigning for the cause by outraging public decency.Source: orange.com