The recall for free repairs covers the Toyota FCHV vehicles whose lease contracts took effect between 2002 and June this year, the officials said.

Fuel-cell vehicles are powered by electricity generated through a chemical reaction between hydrogen and oxygen and emit only water as a waste product.

Automakers have yet to overcome various technical problems before developing a fully reliable vehicle. Toyota has so far carried out three recalls.

The hydrogen leak was discovered in a vehicle leased to a U.S. university.

Toyota decided to recall the 14 units of the older FCHV model to "take all possible measures" to prevent any malfunctioning, an official said.