An envelope containing a letter and white powder was opened by a Dedham Middle School secretary Tuesday afternoon, just hours after a similar package was received at an elementary school in Milford, authorities said.
The FBI is now looking into reports that envelopes with suspicious white powder inside were sent to schools around New England on Tuesday.
Authorities said letters were sent to schools in Goffstown, N.H.; West Warwick, R.I.; and Fort Kent, Maine, as well.
“At this point, all field tests have been negative, and there is no immediate threat to public safety,’’ FBI spokesman Greg Comcowich said. “Additional testing will be done at state labs.’’
In Dedham, Fire Chief William Cullinane said that as soon as the school employee realized that the envelope contained powder, she notified officials and did not move the item.
“The letter remained isolated and contained, as did the person who opened it,’’ Cullinane said.
After investigating envelopes sent to the Dedham and Milford schools, the State Fire Marshal’s office sent advisories to all fire departments, police departments, and school systems alerting them to the incidents.
Letters were sent to Goffstown, N.H.; West Warwick, R.I.; and Fort Kent, Maine, as well.
“They are very similar in nature, in the description of the letters that were received by both schools,’’ State Fire Marshal Stephen Coan said. “Because of the similar characteristics, we also notified the proper federal authorities for further investigation.’’
Coan said the letters had an address and a return address, though he declined to provide further details on where they had been postmarked.
The FBI also declined to provide information on the origin of the letters.
Milford police Sergeant Michael Jones said Tuesday evening that the powder has been identified as corn starch.
He said the white envelope containing the substance was found near the principal’s office at Memorial Elementary School at about 11 a.m. and did not leave the office where it was opened.
Parents were notified about the incident via a reverse-911 call, he said.
Students at Dedham Middle School remained in their classrooms until about 2:30 p.m., then quickly filed past a handful of reporters and numerous fire trucks and police officers to their waiting buses.
A number of them took out cellphones and began taking photos of what was happening and asking questions of principal Deb Gately, who told them that there was never any danger and that the law enforcement presence was procedural.
An e-mail about the incident was sent to parents, and the school remained open as a polling station to residents voting in the presidential primary.
Comcowich said the FBI’s Boston field office is coordinating with other states where they are investigating reports of similar envelopes Tuesday.
“We take these incidents as very real, even if it turns out to be hoax letter,’’ he said. “It is a serious crime and takes up the valuable resources of local, state, and federal agencies that respond.’’