Hundreds of people are searching for a missing 55-year-old Wall Street Journal reporter who left his New Jersey home for a walk on Saturday and never came back.
Sources close to the family told NBC News Thursday that the missing man's credit card was used in Mexico Wednesday night. The family believes that his coverage of OPEC may be related to his disappearance.
The Journal said 55-year-old David Bird covers energy markets for the paper. He has also worked for The Associated Press and the Trenton Times.
Bird was last seen wearing a red jacket, jeans and sneakers, and left his home without his phone "for a short walk," according to the Journal.
He and his wife had been putting away Christmas decorations in the afternoon when he said he wanted to get out for a quick walk, the Journal said. Bird's wife called police two hours after he left the house.
Authorities say the father of two regularly hikes the trails along Hick's Tract in Millington. Hundreds of volunteers on foot, helicopter and horseback have been searching the woods in that area. The Morris County dive team is also searching nearby waterways.
"It's a miserable job but somebody's got to do it and somebody's got to get this guy so his family can have some closure," said volunteer Tyler Sims of Boonton, N.J.
"I'll be out here all night if they ask me to," he added.
Logan Hill Township Police Chief Michael Mazzeo said: "We're going to stay optimistic because we have not received any information that would show us anything otherwise."
Bird's sister-in-law said the family could not make sense of his disappearance.
"It's completely not like David," Chris Fleming told NBC News. "He's a very loving family man. Worked in the city, Boy Scout leader. Everything, it just makes no sense."
The Journal said Bird ran the 2013 New York City marathon and is an avid hiker and camper.
"This is so unlike him it's unbelievable to me," Jim Caparoso, a friend, told the newspaper. "If he was stuck somewhere, he knows how to shelter himself enough out of the elements. He knows how to signal if he can."
Gerard Baker, managing editor of the Journal, said, "our thoughts are with his family and we are working with the Long Hill Township Police Department as they continue their search."
-- Gus Rosendale contributed to this report.