RELATED: Timeline of Peninsula murder mystery
Friends say Keith Green crossed the street from the apartment complex where he lived to meet someone outside the Pancake House around 10:15 p.m. Thursday. He was wearing black sweatpants and a white zip up shirt. He hasn't been seen since.
Friends spent the day wallpapering Millbrae with missing person posters for the 27-year-old.
"He just vanished and (is) nowhere to be found," said friend Shawna Rosenberg.
Green was the best man at Rosenberg's wedding two years ago.
"There's so many stories going on I don't know what to believe," she said.
Green has distinctive neck tattoos. His roommate tells me he was wearing black sweatpants and a white zip up pic.twitter.com/shmBMhiNEF— Melanie Woodrow (@MelanieWoodrow) May 2, 2016
Detective Salvador Zuno with the San Mateo Sheriff's Office says, "His cellphone was found the next morning unattended in San Francisco's Golden Gate Park."
Detectives say a hiker found the phone but it's unclear how it got there. Green left some key items behind at the apartment complex where he stays, which is across the street from the Pancake House.
"He left his car and his wallet so that raised some suspicion with us," said Zuno.
Suspicious to detectives, but not ominous.
Green was best man in friends' wedding -- "He was so kind hearted." pic.twitter.com/XiEhlt4ScT— Melanie Woodrow (@MelanieWoodrow) May 2, 2016
"As of right now we have no information that suggests any foul play of any kind," said Zuno.
Green had been staying with family friend Angela Dunn the last six months.
"We're all just trying to do everything we possibly can to find Keith and reunite," she said. "He's a little bit like having a grandson."
According to Dunn, he was going to meet his ex-girlfriend to work out a custody issue.
"I gave him a hug and said, 'Be true to yourself and be strong,'" she said.
Friends says they are desperate to find the young father of two
"He has two beautiful daughters that need their dad big time," said Rosenberg.
They're hopeful someone will recognize him from pictures and call detectives.
Click here for full coverage on the investigation into the death of Millbrae father Keith Green.