MEXICO CITY—Dozens of journalists and human rights defenders in El Salvador had their cellphones repeatedly hacked with sophisticated spyware over the past year and a half, an internet watchdog said Wednesday. Reporting on its latest findings about use of the Israeli firm NSO Group’s Pegasus spyware, the University of Toronto’s Citizen Lab said it had identified a Pegasus operator working almost exclusively in El Salvador in early 2020. While the researchers could not conclusively link the hacks to El Salvador’s government, the report said “the strong country-specific focus of the infections suggests that this is very likely.” Sofía Medina, spokeswoman for President Nayib Bukele, said in a statement that “El Salvador is no way associated with Pegasus and nor is a client of NSO Group.” She said the government does not have licenses to use this type of software. The government is investigating the use of Pegasus to hack phones …