(Sharecast News) - Highlands Natural Resources announced on Monday that gas sales from all eight wells at the East Denver project had now begun, following completion of the gas pipeline.The London-listed natural resources company said that would add to the "robust" oil revenue it was already receiving from the eight producing wells at the project.Highlands holds a 7.5% interest in each well on the acreage."The directors look forward to updating the public about the initial production rates in due course," the Highlands board said in its short statement.