Authorities in Geneva raised the city’s level of alert and deployed additional police officers Thursday in an apparent search for terrorist suspects. The Geneva office of security said that as part of the investigations following the Paris attacks, it had been notified by Swiss federal authorities that “suspicious individuals” may be in the city or surrounding areas.On the basis of that information, Geneva police were conducting investigations, “in collaboration with national and international services,” the office said.A spokeswoman for the Geneva security office, Emmanuelle Lo Verso, said later that Geneva’s alert level had been raised from 2 to 3 on a scale of 5. She said it was “in the context of” the Paris attacks but did not directly connect the alert with those events.A spokeswoman for the Swiss federal police told Reuters, however, that she had no information connecting the alert to the series of coordinated assaults in and around Paris that killed 130 people last month.Lo Verso declined to comment on Swiss media reports that police had arrested one of several suspects they were seeking or to specify the nature of the threat that had prompted the alert.The Geneva prosecutor’s office said in a statement issued later Thursday that on the basis of information provided by police it had opened an investigation of “criminal preparatory acts.”Signs of the increased security were visible around Geneva, as guards equipped with submachine guns took up positions at the entrance to the United Nations office.The alert came as the city prepared for talks scheduled for Friday on Syria between senior American and Russian officials, as well as the U.N. special envoy for Syria, Staffan de Mistura.The U.S. undersecretary of state for the Near East, Anne W. Patterson, will attend the talks, which diplomats said would be low-key consultations to prepare for further multilateral discussions.Separately, the federal public prosecutor’s office in Belgium said Thursday that it conducted three searches in and around Brussels.No one was arrested, and no arms or explosives were found, the prosecutor’s office said. Belgium has emerged as a crucial part of the investigation into the Paris attacks. -2015 New York Times News Service..