FIRST ON 7: An embarrassing lapse in security has allowed a highly dangerous armed robber to flee authorities, with fears he's on his way to kill two police officers.

Authorities have known for more than two days that Jason Robert Herbert had escaped

his lodgings near Newcastle.

He had been living under supervision, having served eight of fifteen years' jail for armed robbery and grievous bodily harm.

After escaping authorities a first time in July, Herbert was captured and imprisoned at Parklea for four months, then released only two weeks ago, with an electronic monitor to track his movements.

But at 1am on Saturday, it was as simple as cutting the device from his leg and taking off for a second time.

The Parole Authority wasn't aware until hours later, and our broadcast tonight is the first the public is even being told about it.

The escapee's brother, Troy, was killed on his motorbike three years ago trying to outrun police.

Jason Herbert has made many threats to kill the police officers who chased him and it's feared that's what he's on his way to do.

Police in Perth have been informed, and the officers are being offered protection.

Prison bosses here have ordered an urgent review into how badly the satellite tracking failed them in this case.

In the meantime, Herbert is considered armed and dangerous. Anyone who recognises him is asked to steer clear, and call CrimeStoppers on 1800333000.