There is not enough "credible evidence" to charge former U. S. Vice President Al Gore for allegedly groping a massage therapist, Oregon prosecutors said on Friday.

The Portland Oregonian has reported that Police in Portland reopened the investigation into Gore's 2006 encounter with Mollie Hagerty a month ago, the day the National Enquirer ran a story detailing her allegation. But Multnomah County Senior Deputy District Attorney Don Rees found Hagerty's story dubious on a number of grounds.

Rees, in a memo to the district attorney, said Hagerty acknowledged she called Gore after leaving his hotel and told him "to dream of red-headed women tonight." At the same time, she said he had groped her and tried to kiss her against her will and that she was afraid of him.

It has also been reported that there was little or no corroborating evidence. A test for semen on a garment Hagerty said might have been stained turned up nothing, and employees at the hotel told conflicting stories. Gore has repeatedly denied the allegation.

Since losing the 2000 presidential election to George W. Bush, Gore has won a Nobel Peace Prize and Academy Award and, most recently, separated from his wife, Tipper.

The former vice president "respects and appreciates the thorough and professional work of the Portland authorities and is pleased that this matter has now been resolved," Kalee Kreider, a spokeswoman for Gore, told The Washington Post. (With Inputs from Agencies)