Paul Walker's co-stars 'too distraught' to film

Production on the upcoming blockbuster, which began filming in September, is expected to be delayed after the star, 40, was killed in a crash at a charity car show in Santa Clarita, California, on Saturday.

One source said: "No one wants to even think about the movie. Period."

Other sources also told gossip website TMZ.com that the Paul was scheduled to shoot key scenes for the film this week in Atlanta, Georgia.

The insider said that several members of the cast and crew, who were supposed to fly to Atlanta this weekend to resume filming on Tuesday, said they won't be returning to the set anytime soon as they are "too distraught" to work and expect the production will be halted.

Universal Studios, the company behind the film series, has yet to comment but sources said that this week's scenes all focused around Paul so the script will require some major rewrites.

Paul's co-stars Dwayne 'The Rock' Johnson and Vin Diesel paid tribute to the late actor shortly after news of his death broke.

Dwayne tweeted:

All my strength, love & faith to the Walker family during this heartbreaking time. We find our strength.. in his light. Love you brother.

— Dwayne Johnson (@TheRock) December 1, 2013

Meanwhile, Vin Diesel posted on Instagram: