Federal authorities and company representatives are investigating the cause of a flash fire that injured seven contract workers at Sunoco Logistics’ Nederland Terminal Friday night.

Jeff Shields, communications manager for Sunoco Logistics Partners LP., said in a prepared statement they were alerted of the fire around 9 p.m. Friday at the Nederland Terminal. Seven employees with L-Con Inc. were injured, four of them critically, in what appeared to be a flash fire involving a crude oil pipeline connection.

Three of the injured were transported to burn centers via helicopter and four by ambulance to area hospitals.

“We don’t know the actual cause of the fire but we do know there was crude oil present and welding was going on but the exact cause of ignition is part of the investigation,” Shields said via phone on Saturday.

The incident has not significantly affected operations in any way, he said.

Occupational Safety and Health Administration officials were on site Saturday as part of the investigation.

Shields said construction crews were working on connections to some new tanks and internal piping within the plant.

“Sunoco Logistics will work with the contractor, L-Con Inc., to investigate the cause of the accident and support those injured and their families,” he said. “Our prayers are with them.”

There was no impact to nearby residents.

Sunoco offered thanks to Nederland Police Department, Nederland Fire Department, Jefferson County Sheriff’s Office, Jefferson County Office of Emergency Management and

Acadian Ambulance for their timely response. The U.S. Coast Guard was also on site Friday.

The current condition of the injured workers is not known as of Saturday afternoon.

Sunoco Logistics’ Nederland Terminal handles crude oil, condensate, naptha and base and extract oils and has numerous connections to major pipelines including the Strategic Petroleum Reserve and is also the southern end of the Keystone pipeline from Cushing, Oklahoma, according to their website.

L-Con Inc. is a Houston based construction services company that ahs worked with heavy industry for about 20 years, according to their website.

Mary Meaux: 409-721-2429

Twitter: @MaryMeauxPANews