Police say at least six people have been killed and three others hospitalized with severe injures after a bus caught fire in a town west of the Swiss capital. Police spokesperson Frederic Papaux of the Fribourg canton, or region, said an unspecified “voluntary act” could be the cause of the inferno Tuesday evening in the town of Kerzers, about 25 kilometers (15 miles) from Bern, the capital. The regional transport bus is operated by PostBus, which is affiliated with the national postal service. Images from the scene on Swiss media showed flames tearing through the bus. “After rushing to the scene, rescue teams noted that the vehicle was totally engulfed in flames,” the regional government said in a statement.