A preliminary investigation has found that a gasket failure caused a chemical gas leak that forced the temporary closure of a heavily used bridge connecting Delaware and New Jersey on one of the busiest travel days of the year.

Officials with Croda Inc. said Tuesday that initial findings show that an incorrect gasket fitted on a pipe during construction of its Delaware ethylene oxide production plant failed Sunday.

The company is sending the gasket to independent experts for analysis and confirmation. Production of ethylene oxide, which is highly flammable, has been suspended while other equipment is inspected over the next two weeks.

The leak forced the precautionary closure of the Delaware Memorial Bridge for several hours as the Thanksgiving holiday weekend wound down.

It is the only bridge in Delaware that connects to New Jersey, and is primarily used by travelers coming from 95 to the state. It also feeds into the New Jersey Turnpike and I-295.