JALALABAD, Afghanistan — At least 16 civilians were killed Wednesday in a complex attack on a construction company in eastern Afghanistan, officials said.

The attack started with an early morning suicide explosion at the entrance of a construction company in Jalalabad, the capital of Nangarhar Province. After the blast, four armed attackers wearing suicide vests entered the compound and shot employees of the company, prompting a firefight with Afghan security forces that lasted more than five hours, said Attaullah Khogyani, a spokesman for the provincial governor.

The office of the company, Entire Builders and Engineers, is close to the provincial airport, where American and Afghan forces are stationed.

“All those killed were employees of E.B.E., nine civilians were also wounded in the attack, two of them in critical condition” Mr. Khogyani said. “All five attackers were killed, a vehicle laden with explosives, two suicide vests, rockets and mines were discovered in the scene of attack by security forces.”