A Mill Valley man rescued from the side of Mt. Tamalpais Tuesday morning after sliding about 100 feet downhill had been running along a trail and fell into water on his way to catch a bus, his wife said.

Dennis Klein, who often runs along the mountain near his home, was jogging near the Pantoll Trailhead dressed in jeans and a T-shirt at about 3:30 p.m. Monday and it got dark earlier than he thought, according to Doug Pittman, spokesman for the Marin County Sheriff's Office.

He then fell into a creek, became cold and wet and "it was too dark to move," his wife Lynne Klein said.

As darkness fell, Dennis used his cell phone to call for help, waited and when he spotted a rescue helicopter, he attempted but failed to flag it down, his wife said.

When he tried to go back in the darkness to where he was sitting, he slid 100 feet down the slippery mountain and cut his right arm, Lynne Klein said.

"It was a really good tumble," she said. "He runs there almost every day. I think he was going to go catch a bus at Stinson Beach."

Klein then decided to stay where he was in the dark rather than risk falling again, Lynne Klein said.

Klein was not exactly sure where he was, making it difficult for authorities, including more than 50 search and rescue volunteers from seven local agencies, to locate him in the night, Pittman said.

Sheriff's deputies from Marin, Contra Costa, Napa, Solano and San Mateo counties joined the search, as did firefighters from the Stinson Beach City and Marin County fire departments, Pittman said.

The California Highway Patrol also pitched in with a search helicopter equipped with an infrared night vision viewer, but the tree line was too thick to find Klein, Pittman said.

At about 2:30 a.m., a group of deputies from Napa County, wearing helmet flashlights, happened on Klein and since he was not able to walk, they carried him to safety. He was able to leave by 6 a.m., Pittman said.

At first, Klein, who suffered a laceration to his right arm during the fall, refused medical treatment, but later he had it seen at a hospital at the urging of friends, Lynne Klein said.