An Oak Bluffs firefighter was listed in serious condition in a Boston hospital Thursday following a freak accident over the weekend involving the motorcycle he was operating.

Eric Voshell, 37, was riding with his passenger Heather Chartier along Sea View avenue near Lola’s restaurant in the early hours of Sunday morning when the incident occurred.

Oak Bluffs police said Ms. Chartier was wearing a sweater that became caught in the back wheel, causing the wheel to lock up and the operator to lose control of the bike. “Speed doesn’t seem to be a factor,” Oak Bluffs police Lieut. Timothy Williamson said Tuesday.

Ms. Chartier, a resident of Manchester, N.H., suffered minor injuries.

Mr. Voshell was more seriously hurt and was transported by ambulance to the Martha’s Vineyard Hospital. He was later transported by ambulance to Massachusetts General Hospital in Boston, where he was listed in critical condition Tuesday morning.

Lieutenant Williamson said both victims were wearing helmets, but not the type approved by the U.S. Department of Transportation. The motorcycle was a Harley-Davidson.

Mr. Voshell has been a call firefighter with the Oak Bluffs fire department for six years.

Oak Bluffs fire and ambulance chief John Rose was among the medics answering the emergency call Sunday morning.

He said it was a difficult scene, working to save the life of one of their own.

“Everybody did a great job with the circumstances we were faced with there,” Chief Rose said. “It’s just a really tough scenario for everyone involved. It’s one of the difficult challenges we face. We’re such a small community and you know so many people. You never know when you pull up to something if it’s going to be somebody you know, or one of your loved ones.”