STOCKTON (AP) — Authorities are offering a $50,000 reward for information leading to the arrest and conviction of a fourth suspect in connection with a bank robbery that spun into a police chase and deadly shootout.

The FBI said Thursday it will be contributing $20,000 to a reward fund that also includes $20,000 from the Bank of the West and $10,000 from Stockton Crime Stoppers.

Officials say they want to find the driver who dropped off three armed robbers outside the bank last Wednesday before driving away in a black Buick.

The car was found two days later.

Two of the robbers and one hostage were killed during the shootout. The third robber who police said used the hostage as a human shield faces murder and attempted murder charges.