Bruce Clawson of the Texas City Office of Emergency Management said no injuries were reported in the latest explosion at the 1,200-acre complex.
All BP employees had been accounted for, Clawson said he was told by BP officials. All fires stemming from the explosion Thursday evening were extinguished early Friday morning.
Officials said the incident occurred about 6 p.m. Texas City Fire Chief Gerald Grimm told the Houston Chronicle the fire was confined to a specific area.
Residents who live near the refinery reported hearing and feeling the explosion from their homes.
The explosion, however, had nowhere near the intensity as the blast in March, which killed 15 contractors and injured more than 170 workers, according to a UPI report.
The refinery processes 433,000 barrels of crude oil a day and 3 percent of the nation's gasoline.
The latest incident comes as BP faces scrutiny for its environmental and safety record. The company leads the nation in refinery deaths during the last 10 years, with 22 since 1995. In 2003 and 2004, its Texas City refinery â€” built in 1934 and the third largest in the U.S. â€” had more than 100 accidental releases of air pollution.