A fed-up cyclist, frustrated with how long bomb-defusal experts were taking to deal with a suspicious package, has been caught on camera taking matters into his own hands.

An unattended backpack left on a Milwaukee street was reported to police at about 7am on Monday morning. By 9am the entire area was taped off as a professional bomb squad cautiously studied the bag and moved it into the middle of the road, away from surrounding buildings.

In the video, a man on a bike, visibly frustrated, can be seen riding onto the scene towards the bag and haphazardly emptying the bag’s contents onto the ground for all to see – finding a water bottle and a few items of clothing.

Rather than receive a pat on the back from police officers and the bomb squad for bravery or potentially saving hours of time, the cyclist gets spear-tackled into the ground and then handcuffed.

Witnesses told US media outlets they heard the man riding past moments before saying, “I’m going to defuse this situation.”

"If I would have saw him coming down the sidewalk earlier, I would have tried to stop him. It's a scary situation,” Robert Harris said, who initially called authorities about the bag.

“You don't know if it's a bomb or backpack. When he went and did it, I thought 'oh no'. It's not going to end well. It's going to end bad."

The man was arrested and taken into custody though it’s still unknown whether or not he’ll face charges