"Fast & Furious" costar Tyrese Gibson was visibly grieving during a visit Sunday to the crash site where Paul Walker was killed, PEOPLE reported.

Gibson posted a picture on Instagram of himself holding a piece of the wreckage.

"I will keep your energy with me forever #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 in the caption.

The actor brought flowers and cried at the crash scene, where 40-year-old Walker died Saturday afternoon. He was in a car that crashed and exploded in Santa Clarita, Calif., according to PEOPLE. The car's driver was killed as well.

When they arrived, deputies found the vehicle engulfed in flames," the police said in a statement. "The Los Angeles County Fire Department responded, extinguished the fire and subsequently located two victims inside the vehicle. The victims were pronounced dead at the scene." 

Walker, who had been filming "Fast & Furious 7" for a scheduled summer 2014 release, was "attending a charity event for his organization Reach Out Worldwide" around the time of the crash, according to a post on his official Facebook page.

Gibson earlier posted a photo with Walker, who is survived by his 15-year-old daughter, Meadow Rose.

"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," Gibson wrote in the caption. "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 and family...

"#HeartOfAnAngel13YrsFamilyForeverWeJustCelebreatedYour40thBirthday..... My God... My God... I can't believe I'm writing this." 

See Now: OnePlus 6: How Different Will It Be From OnePlus 5?