( dpa ) - Three men were arrested Tuesday on suspicion of involvement in an armed robbery and bomb scare in the Swedish west- coast city Gothenburg earlier in the day. Police chief Krister Jacobsson described the overnight heist of the city's main post terminal as "spectacular," and said it caused major disruptions for commuters and inhabitants. Early Tuesday, several masked robbers armed with rifles entered the terminal building and ordered the 10 postal workers to lie on the floor, but no one was reported physically hurt. Spokesmen for the postal services and police said the building is mainly used for regular letters and packages. Several cars were set ablaze on nearby access roads after the suspects fled. Several suspicious devices including a box marked "bomb" were also spotted. The robbers also spread metal spikes at several locations, likely to prevent pursuing vehicles. Jacobsson told Swedish television news Tuesday evening that the search for other suspects was continuing and declined to comment on what the robbers may have taken. Police believed at least 10 people took part in the robbery and that five vehicles were set ablaze, said Klas Friberg, who is leading the investigation for the Gothenburg police. The suspects also placed several suspicious devices that were treated as bombs, Friberg told reporters. One device was sighted in a car parked near the entrance to the main police garage in what was likely an attempt to delay police response. In addition to cordons, police evacuated several apartment buildings. Bomb disposal experts used a special remote-controlled robot to destroy the devices and reinforcements were sent from Stockholm and Malmo. The cordons disrupted several tram and bus routes, causing delays in the morning rush hour. At the end of last year, there were several shootings in the west- coast city, including at police helicopters parked outside a hangar overnight in Gothenburg City Airport.