California's two U.S. senators want the Marine Corps to review its entire fleet of F/A18-D Hornet jets for possible problems after one of the jets crashed into a home and killed two young girls, their mother and their grandmother.

In a joint letter Wednesday, Sens. Dianne Feinstein and Barbara Boxer asked Gen. James Conway, Marines commandant, to quickly complete the investigation of Monday's crash and make the results public.

"We can all agree that in urban areas like San Diego County, where the military and civilian populations closely coexist, it is absolutely vital that all precautionary steps are taken to ensure the safety of both our civilian and military residents," the letter read.

Marine spokesman Maj. David Nevers said authorities would thoroughly investigate the cause of the crash but gave no indication of plans for a broader probe of the fleet's 635 Hornet jets.

"While there is no reason to suspect a systemic engine-related problem that might affect the entire fleet of F/A-18s, safety is always of paramount concern," Nevers said. "If the investigation were to point to a wider problem, we would act swiftly to address it."

Initial reports suggest the jet may have suffered engine failure on a training exercise after takeoff from the carrier USS Abraham Lincoln about 50 miles offshore from San Diego. The jet was returning from an offshore training mission when it clipped a tree and slammed into the neighborhood about two miles from Marine Corps Air Station Miramar.