America's top diplomat was in Cambodia Tuesdayon the second stop of his trip to Asia.Secretary of State John Kerry met with Cambodian government leadersand opposition party members in Phnom Penh.Kerry said the country has improved its human rights recordand made economic progress.But he said he told officials that he was concernedabout continued human rights violations.Kerry met separately with Prime Minister Hun Senand acting opposition party leader Kem Sokha.After the meetings, the U.S. official said that"democratic governments have a responsibilityto ensure that all elected representativesare free to perform their responsibilitieswithout fear of attack or arrest."Seventeen opposition members and activists are jailed in Cambodia.Opposition leader Sam Rainsy is living in self-declared exileto avoid charges made against him.Many observers believe the charges are unfair.And rights groups say the United Statesshould not improve relations with Cambodiauntil its leaders guarantee reforms.Secretary Kerry also praised Cambodia for its economic progress.He told the prime minister that"Cambodia has experienced remarkable growth.You have seen incredible changes-- not just here in Phnom Penh,which moved from a 350,000-person war-torn cityto a much more modern city of 2.2 million people."