ACTON, Mass. – A three-alarm fire moved quickly through an Acton home early Wednesday morning, killing two occupants, officials said.

The victims, described by broadcast outlets as an elderly couple who had lived in the home for a long time, were found dead on the second floor of the single-family house on Captain Forbush Lane, state Fire Marshal Stephen Coan said.

Their identities were not immediately made public. The medical examiner is conducting autopsies to determine the cause of death.

Firefighters, alerted to the blaze by a neighbor at about 1:30 a.m., arrived on the scene to find the home fully engulfed.

The fire’s cause is still under investigation but does not appear to be suspicious, Coan said. Coan said he is also trying to determine whether the home had smoke alarms.

Coan said he is concerned because 26 people have died in fires in Massachusetts already this year, far ahead of the five-year average. There were 43 fire deaths in the state all of last year he said.

“We’ve done a good job in recent years of driving fire fatalities down with the widespread use of smoke alarms, laws that require new construction to have smoke alarms, and getting out the educational message, telling people not to overload electrical outlets,” he said.

The rash of fire deaths early this year are “a call for people to take the time to make sure that smoke alarms are in place and good practices are being observed,” he said.