The owner of several Southern California trucking companies pleaded guilty to five felony charges involving tax evasion, COVID-19 relief fraud and an illegal repair of a tanker that resulted in a fatal explosion, federal prosecutors said.

Carl Bradley Johansson, 63, of Newport Beach entered the pleas late Wednesday, the Los Angeles U.S. Attorney’s Office said in a statement.

The explosion occurred in 2014 when two employees were ordered to begin a welding project on a cargo tank that had not been completely purged of fumes and crude oil. One worker was killed and the other was seriously injured.

The other felony counts involved failing to file income tax returns for six years and fraudulently obtaining more than $667,000 from the Paycheck Protection Program.

Three companies Johansson controlled also pleaded guilty to various charges on Wednesday. A safety manager at one of the companies pleaded guilty to conspiracy in August and another defendant faces trial in January.