"I will keep your energy with me forever", Fast & Furious star Tyrese Gibson wrote yesterday on Twitter.  Gibson was writing in memory of his fallen co-star Paul Walker who passed away in a single-car crash Saturday near Los Angeles.

40-year old Walker's tragic death on Saturday has left his Fast & Furious family in mourning. A visibly distraught Gibson was in tears as he visited the crash scene on Sunday.

Gibson arrived with a flower in his hand to a site already decorated with candles and photos memorializing Walker.

 

Tyrese Gibson with Paul Walker, Instagram

Continuing to express his pain on Instagram, #AshesOfAnAngel fast family around the world we live you and we love you Paul is the heartbeat of this franchise and were gonna see to it that his energy and presence lives on forever #myhearthurtssobad," he wrote.

After learning of his death on Saturday, Gibson wrote:

"My heart is hurting so bad no one can make me believe this is real Father God I pray that you send clarity over this cause I just don't understand My heart hurts it's broken no one can convince me that this is real.... Prayer warriors please pray real hard for his only child, his daughter...My God... I can't believe I'm writing this."

Investigators say speed was a factor in the crash, which occurred in Valencia, about 30 miles northwest of downtown L.A.

Actor Paul Walker Dead at 40

Both Walker and Roger Rodas, the friend suspected of driving the red Porsche Carrera GT --died in the fiery accident.

Autopsies on both men are not expected to be conducted for a couple of days, due to the condition of the bodies. The Los Angeles County Coroner's Office says dental records are needed to positively identify the victims.

Walker was in the process of filming the next installment of the Fast & Furious movie franchise.  Producers will have to work with the script to finish the film without their lead star.