Arson is to blame for a series of recent brush fires in Lynn, Massachusetts, investigators say.
The Massachusetts Fire Marshal's Office said Wednesday that at least eight fires across about 400 acres had been intentionally set in the last several days.
Crews first started fighting fires in the Lynn Woods Friday, continuing to battle the flames Saturday. On Monday, authorities said the fire broke out of containment, burning in the woods and sending more smoke into the sky.
Much of New England has been under very high brush fire danger.
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"It's just kind of too coincidental with that many fires in such a short amount of time," said Lynn Fire Chief Daniel Sullivan.
Helicopters were used to dump water from Walden Pond onto the fire.
On Monday, Lynn banned people from going on the trails north of the pond, closing them "until further notice." That pond is different from the Walden Pond in Concord made famous by Henry David Thoreau. They remain closed as of Thursday.
"The quantity of fires, remote from each other is one indication and then what our investigators do is they look at burn patterns," said Sullivan. "Fires burn in somewhat predictable manner and using topography and the environmental conditions they can use some techniques to see if they had all started from one fire and burned back to a certain area or started and then kind of merged into one as the winds and the topography kind of steered into a certain direction."
Sullivan said any observations that appear suspicious or out of place could be helpful to the investigation.
"People who do this stuff sometimes like to brag about it, so offhand comments might be interesting to our investigators, people that you don't normally see going into these areas or out of areas maybe timing, as well," he said. "It's not just the entry points where the parking lots, but we have a lot of neighbors that have surrounding access to the woods so if they have seen anything or people coming and going that normally they hadn't seen that might be interesting to our investigators."
"About 40% of Massachusetts home are in or near wildland areas," Fire Marshal Peter Ostroskey said in a statement Wednesday. "Setting a fire in this environment is a particularly dangerous act, especially under the current weather conditions. If you have any information that can help investigators, please share it today."
Authorities are asking anyone with information to call the Massachusetts State Police Fire and Explosion Investigative Unit 978-567-3310 or the Arson Watch Reward Program at 1-800-682-9225.