A Chula Vista resident was killed Friday morning after his SUV veered off state Route 54 in National City, plowing through a fence and plunging into the Sweetwater River, officials confirmed.
At around 6:20 a.m., Caltrans San Diego tweeted it was closing the westbound state Route 54 ramp to southbound Interstate 5 due to the collision. All lanes were temporarily blocked off to traffic and a Sig Alert was issued.
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The California Highway Patrol said the crash was reported just before 5:40 a.m. off SR-54, west of National City Boulevard and east of I-5. One of the witnesses who reported the incident said she was walking on a nearby path when she spotted the driver plunging into the water.
CHP officials said the vehicle -- a grey Lexus SUV -- became submerged.
CHP shut down the westbound SR-54 ramp to southbound I-5 for several hours so emergency crews could move into the scene. Traffic was backed up to Highland Avenue.
The National City Police Department soon confirmed one person was dead in the crash. CHP later confirmed the person who died was the driver, identified only as a 69-year-old man from Chula Vista.
National City Fire Department Capt. Jeremy Day said the crash was reported by two separate passersby on the bike path. A third passerby stayed at the scene to point out the car to officials.
Day said the Lexus SUV was, at first, difficult to see in the water because of the darkness. The driver had crashed through a fence and drifted down an embankment before crashing into the water.
The SUV was upside-down, it's rear wheels partially peeking from the water.
Eventually, firefighters from National City and Chula Vista were able to get access to the river. They opened the doors of the SUV to search for survivors.
San Diego Lifeguards soon joined the search.
About 200 yards east of the SUV, lifeguards found the floating body of the driver. He was declared dead at the scene; his name was not immediately released by investigators.
Divers with the Harbor Police Department also helped, scouring the water to make sure there were no other bodies near the crash site.
CHP officials said the driver was the sole person inside the SUV and no one else was found inside the river. No other cars were involved in the deadly crash.
The investigation is ongoing. CHP officials said toxicology reports are being conducted to determine if drugs or alcohol played factors in the deadly crash.
Check back for updates on this developing story.