A senior Pakistani official confessed on Saturday to helping manipulate results in the country’s elections — a startling claim strengthening a sense that the vote was among the least credible in Pakistan’s history, and deepening the turmoil that has seized the country ever since people went to the polls this month.

The official, Liaquat Ali Chatha, is a top administrative official in Punjab Province overseeing Rawalpindi, a garrison city where the military has its headquarters, and three adjacent districts. He said he would resign from his position and turn himself in to the police.

“We converted losers into winners, reversing margins of 70,000 votes of independent candidates for 13 national Parliament seats,” he said at a news conference on Saturday, referring to moving votes from independent candidates aligned with Imran Khan, the former prime minister whose party the military had sought to sideline ahead of the vote. He suggested other high-ranking officials had been a part of the scheme, and said he was unable to sleep at night after “stabbing the country in its back.”