 A policeman guarding the Israeli embassy building was shot in the neck with a crossbow. He then fired back, killing the assailant, who was later identified as a convert to Islam. Serbia's prime minister described the shooting as the work of one man. But a number of people have been arrested, and police say they're still looking for others who may have been involved. The country's interior minister, Ivica Dacic, also seemed to suggest there might be a wider problem.