LOCKPORT, La. (AP) — Louisiana-based Bollinger Shipyards, a major defense contractor, has agreed to purchase four Mississippi shipyards from subsidiaries of Singapore-based Singapore Technologies Engineering Ltd., the companies announced Monday.

The $15 million purchase of VT Halter Marine, Inc. and ST Engineering Halter Marine Offshore involves 2 shipyards in Pascagoula and two dormant yards north of Pascagoula. They will be renamed Bollinger Mississippi Shipbuilding and Bollinger Mississippi Repair. The deal could also mean an additional $10 million for ST Engineering from future shipbuilding contracts for Halter Marine.

Bollinger said in a news release it expects the deal to be completed by the end of the year.

“The addition of VT Halter Marine and STEHMO in Pascagoula, Mississippi is strategic as it further strengthens our position in the industry and U.S. defense industrial base by allowing Bollinger to expand our footprint, capabilities and suite of innovative solutions that we can provide to our customers,” Bollinger CEO Ben Bordelon said.