A day after Ferromex said it would temporarily halt service on 60 trains that go to the U.S. border in response to a number of incidents involving migrants hitching rides and getting hurt, the Mexican transport firm said some of its trains had begun running north again. Reuters reported Wednesday that Grupo Mexico, Ferromex’s parent company, said freight operations had restarted on routes where there was no “heightened risk.” Grupo Mexico did not say how many trains were still suspended from service, nor how it had measured the risk. On Tuesday, Ferromex had said there had been roughly a “half-dozen regrettable cases of injuries or deaths” among migrants climbing aboard its freight cars. A spokesperson for Grupo Mexico told NBC News that an “unprecedented” number of unauthorized hitchhikers had led Ferromex to suspend its services for the first time ever. Ferromex is the largest freight company in Mexico, and the company said the stoppage was expected to affect some international trade.