MANTECA — A luxury apartment complex that began construction last June and was expected to be ready for occupancy this summer was devastated by a major fire Sunday morning.

The Tesoro Apartments at Van Ryn Avenue and East Atherton Drive, visible from Highway 120 looking south, lost four structures to the blaze that was first reported shortly before 9 a.m., according to Manteca fire officials. Multiple buildings were fully involved as the first firefighters arrived.

One estimate put the loss at 25 percent of the unoccupied complex covering 7.5 acres that was in the process of completing 154 units. Manteca Fire Marshal Lantz Rey reported there were no injuries during the battle to control the fire.

Manteca firefighters were assisted by crews from Stockton, Tracy, Ripon and Lathrop-Manteca departments, putting 68 firefighters on scene, according to Rey.

The fire is believed to have started on the third floor of one of the buildings under construction. Once on scene, due to the extreme heat, firefighters focused on keeping the blaze from spreading to other buildings.

“Our crews will remain on scene through the night for an extensive mop-up. The cause of this fire is under investigation and anyone with information should contact the Manteca fire marshal at (209) 456-8300,” he said.

Contact reporter Joe Goldeen at (209) 546-8278 or jgoldeen@recordnet.com. Follow him at recordnet.com/goldeenblog and on Twitter @JoeGoldeen.