TOKYO (AFP) - Japanese automaker Honda on Thursday said it was recalling another 4.5 million vehicles globally, as a scare over Takata-made airbags widens.

The move takes to 24.5 million the total number of vehicles that the country's number three automanufacturer has recalled so far.

The defect - thought to be associated with a chemical propellant that helps inflate the airbags - can cause them to deploy with explosive force, sending metal shrapnel hurtling toward drivers and passengers.

"Like other carmakers, we are investigating vehicles on the market in connection with this issue, and we found that some inflators have uneven gas density, which we worry could do some harm," a Honda spokesman said.

"It is a preventive measure and unlike other normal recalls we are not waiting for the full results of the research," he added.

Honda's Japanese rivals Toyota and Nissan last month expanded their huge global recalls, with worldwide totals now well into the tens of millions.