WASHINGTON (Reuters) - U.S. senators called on President Barack Obama’s administration on Friday to impose targeted sanctions on officials in the Democratic Republic of Congo responsible for violence and rights violations amid rising political tensions. Hoping to increase pressure on the government of President Joseph Kabila, three of Obama’s fellow Democrats, senators Richard Durbin, Edward Markey and Christopher Murphy, said on Friday they had introduced a Senate resolution this week calling on Kabila’s government to fulfill its constitutional mandate for a democratic transition of power late this year. They called for targeted sanctions, including visa bans and asset freezes, until Kabila publicly commits to a peaceful transition of power. Their action reflected growing international worry over the situation in the African nation. United Nations Secretary-General Ban Ki-moon on Wednesday voiced concern about reports of rising political tension due to uncertainty about the presidential election.  Dozens of Kabila critics have been arrested since last year as part of what the United Nations and rights groups say is an escalating crackdown on political dissent ahead of a presidential election scheduled for November. Kabila is ineligible to stand for re-election after serving two elected terms, but opponents accuse him of trying to delay the poll to hold onto power. Congo’s highest court ruled last week that the president could stay in power if elections did not occur by the end of his mandate. On Thursday, a protester and a police officer were killed in Goma, in the eastern part of the country, during protests against a possible elections delay. The United Nations said dozens of people were arrested. Opposition leaders accuse Kabila of stalling the vote in order to extend his 15-year rule, which the president denies. Democratic congressional aides said they expected to add more co-sponsors for the resolution after Congress returns from its Memorial Day recess on June 6. There is bipartisan support for U.S. action to address the situation.  Republican Senator Jeff Flake, the chairman of the Foreign Relations Committee’s Africa subcommittee, told Reuters in a brief interview this week that he felt sanctions would be appropriate and had discussed them with U.S. State Department officials. “Hopefully we’re together on this,” Flake said. “I think we will be. We just want to make sure that whatever we do, pushes in the right direction.” 