the start of the year.
The Nasdaq OMX Stockholm exchange cancelled trades worth 160 million Swedish crowns ($24.6 million) in Fingerprint Cards from 10.17 am (0817 GMT) on Friday, just before the false statement was released, until it halted trading 17 minutes later.
The exchange also cancelled 140 million crowns of trades in Fingerprint's rival Precise Biometrics which rose as much as 44 percent when the press release was published.
"Of course we are going to investigate what has happened and we are going to do that with the company in question, the FSA (market regulator) and Cision," Carl Norell, a spokesman for the exchange said.
Trading in both stocks resumed later on Friday. Fingerprint ended the day unchanged at 52.75 crowns, while Precise Biometrics was also unchanged at 2.09 crowns. Cision shares closed 5.3 percent lower.
Reuters withdrew a story it had published based on the hoax press release.
While market manipulation is rare in Sweden, it is not unheard of internationally.
Late last year, a fake press release said internet giant Google was buying wireless hotspot provider ICOA Inc for $400 million.
Shares of ICOA, which is traded over-the-counter, jumped from .0001 cents to .0005 cents before the company's CEO denied the news.
It remained unclear who was behind publication of the Fingerprint Cards press release.
Gunther Marder, an economist at internet bank Nordnet said the perpetrators probably had positions in biometric firms listed on other markets in Europe not in Fingerprint or Precise.
"You would look around the world outside the territory that the Stockholm exchange supervises," he said, adding that sophisticated criminals would know trading in stocks listed in Stockholm would be cancelled.