Richard Walsh, a Massport spokesman, said the jet's auxiliary power unit battery, which is housed in a small compartment known as the aft electrical equipment bay, exploded after crews believed the fire was extinguished.

WSJ: Japan Airlines' Jet Suffers Fire in Boston

Officials had said they were examining the electrical system broadly, but while earlier incidents involved components in the aft electrical equipment bay, located behind the wings, Wednesday's involved a forward bay that until now had been largely free from scrutiny.

WSJ: Boeing Dreamliner Makes Emergency Landing in Japan

One sits underneath the cockpit in a compartment known as the forward electrical equipment bay, which was where Wednesday's malfunction occurred, and a second in the aft bay under the wings, which was the site of last week's fire in Boston.

WSJ: All Boeing Dreamliners Are Grounded

Wall Street analysts have ripped the deal, citing the weak Canadian dollar and Bay's second-tier equipment.

FORBES: Follow Through

Specialist sonar equipment will once again be used to search the mouth of the River Ely in Cardiff Bay.

BBC: Ben Thompson

Its payload bay, meanwhile, is designed to take interchangeable modules so that it can hold whatever equipment is required.

ECONOMIST: Fleets of robot submarines will change oceanography