Hybrid cars are becoming more and more popular with the rising price of gas, but some emergency responders said the technology can create a dangerous obstacle for them.

Firefighters said the electricity used to power hybrids require high-voltage wiring.

That means firefighters can't use metal-crushing or wire-splitting tools to rescue people trapped inside.

"There is a concern with the hybrid cars simply because they do have high voltage systems in them to operate the cars," firefighter B.J. Hyde said.

Firefighters also said the near-silent engine can also make it difficult to determine if the hybrids are shut off.

Departments said they rely on carmakers to keep them up to date on technology.

So far, there have been no reports of injuries involving responders and hybrids.