MEXICO CITY - US Secretary of State Rex Tillerson warned Mexico on Friday to pay attention to Russian meddling in elections around the world, following comments from another US official that there were signs of such interference in the country's presidential race.Speaking in Mexico City, Tillerson said European counterparts had noticed that Russia had had its fingerprints on a number of elections."We hear this from our European counterparts," Tillerson said. "My advice would be ... pay attention to what's happening."His comments followed remarks late last year by US National Security Adviser H.R. McMaster, who said there was already evidence of Russian meddling in Mexican elections set for July.McMaster did not give details of the alleged interference.Tillerson made no reference to alleged Russian interference in the 2016 US election won by President Donald Trump. That involvement included people in Russia buying 3,000 US political ads and placing 80,000 Facebook posts seen by 126 million Americans over two years, Facebook has said.US Special Counsel Robert Mueller is investigating the allegations of Russian meddling in the US campaign, including whether there was any collusion between Trump's team and Moscow.Russia denies that it intervened in the election.The country led by Vladimir Putin has also been accused of intervening in votes in Italy, Finland, Britain and France, among others.Mexico holds presidential and congressional elections on July 1 and so far the frontrunner in almost all polls is left-wing former Mexico City Mayor Andres Manuel Lopez Obrador.An aide to presidential hopeful Jose Antonio Meade, hoping to run for the ruling Institutional Revolutionary Party (PRI), warned in January that Russia could try to benefit Lopez Obrador.Lopez Obrador has made light of the allegation and has since taken to wearing a jacket embroidered with the name "Andres Manuelovich."