Brussels: Amid tight security controls, Brussels airport reopened for three "symbolic" flights on Sunday, 12 days after terror attacks that claimed 34 lives. Three Brussels Airlines flights were scheduled to depart for European destinations, with the first leaving at 11.40 a.m. (local time) for Faro in Portugal, BBC reported. Strict security measures were taken as the airport reopened partially. The passengers were screened on an approach road and again before check in. Both the Brussels attacks on the airport and a metro station on March 22, as well as the November 12, 2015 Paris attacks were claimed by the Islamic State militant group. Airport workers gathered at Zaventem to watch the first flight take off. The other two flights on Sunday are to Turin in northern Italy and Athens. Airport chief executive Arnaud Feist said: "These flights are the first hopeful sign from an airport that is standing up straight after a cowardly attack." Brussels Airlines has estimated that the closure of its hub cost it $5.7 millions a day. The stringent new security checks were put in place after police threatened to go on strike if measures were not improved. Passengers were asked to arrive three hours before their flight departure time. They can get to the airport by car or taxi -- the terminal is still closed to trains and buses. Late on Friday, Belgian officials reached a deal with police unions on enhanced security at the airport. Feist said that he hoped the airport would get back up to full capacity in time for the start of the summer holidays at the end of June.