Observe them

You decide it's too rash to confront them immediately. They could be perfectly normal, law-abiding citizens after all!

"As if." you mutter, when they open the crates. Inside were some strange, dark metal tools. You can't help but feel like they are weapons of some sort. Something fishy was going on here.

Suddenly, a flash of light illuminates the docks. A thug goes flying across the air, trailing smoke. Another flash, and another flying body. The thugs scramble into action, drawing their guns as well as seizing the strange objects.

Soon it's an all out gunfight between the mysterious lightning-flinger and the equally mysterious thugs. A man brought the strange weapon to bear, and shot out a beam of light! You jaw drops in fascination. It slices through the shipping containers like a hot knife through butter. You're grateful you didn't jump in blindly.

However, the other super appears to be in trouble, and is being pushed back by the regular bullets and laser beams.