The sheriff of Putnam County, Georgia, admitted that a pair of inmates who escaped custody after they were accused of killing two correctional officers earlier this week had a 13-hour head start on authorities after they allegedly stole a white pickup truck and switched vehicles before authorities realized it.

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Sheriff Howard Sills and FBI officials described at a news conference Thursday the expanded effort to find Donnie Russell Rowe and Ricky Dubose.

The effort includes a newly created tip line: 877-WANTED2 (926-8332).

Sills said authorities believe the duo stole the white Ford F-250 pickup truck sometime between 10 p.m. and 11 p.m. Tuesday. At the same time, authorities were searching for a green Honda Civic, which was stolen after the alleged shooting.

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“This is the greatest effort I have ever seen, and it’s not just because of the crime,” Sills said. “It’s because the public is in grave danger. These are serious, dangerous hoodlums that need to be apprehended.”

Authorities also announced the reward for the apprehension for the duo has increased to $130,000.

“I’ve worked in law enforcement in this state in some capacity for 44 years, and I can tell you today, there has never been a reward that large,” Sills said.

Rowe and Dubose are accused of overpowering and killing two corrections officers on a bus transporting 33 inmates in Putnam County on Tuesday.

Sills became emotional when speaking about Sgt. Christopher Monica and Sgt. Curtis Billue.

“This black stripe, it’s been on this badge more in the last year than ever before,” Sills said, fighting back tears. “We’ve grown to expect this. We expect to be assassinated at any time.”