(This June 28 story has been corrected to say Fisker recalled thousands of cars, not more than 18,000 cars, earlier in the month of June, in paragraph 8)

(Reuters) - Electric-vehicle firm Fisker is recalling more than 12,000 Ocean vehicles to fix an issue where exterior door handles can stick and fail to open, the company said on Friday, marking its third recall this month.

The U.S. National Highway Traffic Safety Administration (NHTSA) has four open investigations into a variety of issues related to the Ocean SUV that was meant to compete with Tesla's best-selling Model Y crossover.

Once a high-flying EV startup, Fisker filed for bankruptcy protection earlier this month after burning through cash in an attempt to ramp up production and deliver its Ocean SUVs.

"A door that fails to open can prevent occupants from exiting in an emergency, increasing the risk of injury," the regulator said, adding that the company will replace the faulty door handles free of charge.

Fisker in a notice asked its dealers in the United States, Canada and Europe to stop sales of the Ocean vehicles in inventory and inspect for the issue.

The company said in a statement 8,204 Ocean SUVs in the United States, 513 in Canada and 3,806 in Europe were being recalled, taking the total figure to 12,523 units.

Customers have complained widely on social media platforms of issues regarding the key fob not unlocking the car at times and the door failing to open.

Earlier this month, Fisker recalled thousands of cars in North America and Europe due to faulty software and non-compliance with safety standards.

Fisker is the second automaker by famed car designer Henrik Fisker to file for bankruptcy protection. The first outfit, Fisker Automotive, filed for bankruptcy in 2013 after a battery failure in its Karma plug-in hybrid electric vehicle resulted in a recall and substantial associated costs.

(Reporting by Chandni Shah and Akash Sriram in Bengaluru; Editing by Devika Syamnath)