A technology company that as recently as 2015 delivered investors a 1,600 percent stock-price gain now finds its name at the center of a criminal investigation in Scandinavia.

Sweden's crime authority arrested current and former officials at Fingerprint Cards on suspicion of aggravated insider trading, sending shares of the maker of biometric sensors for smartphones to a 15-month low Monday.

"Overall, there have been far too many twists and turns and strange events connected to Fingerprint," Joacim Olsson, chief executive at the Swedish Shareholders' Association, said by phone. "At some level, this indicates that the company hasn't matured to the same degree that it has grown."

Board member Lars Soderfjell and former chief executive Johan Carlstrom were taken into custody, the Swedish Economic Crime Authority said Monday. Authorities became suspicious after trading in Fingerprint shares spiked before a Dec. 8 profit warning that subsequently pushed the stock down as much as 18 percent.

The investigation marks a setback in Fingerprint's attempts to distance itself from Carlstrom, who's also been charged separately for insider trading while he was still CEO. Meanwhile, the company is struggling to stay competitive as rivals offer cheaper alternatives to the technology that brought Fingerprint to fame: sensors used by the likes of LG Electronics and Lenovo Group.

The company says the arrests are linked to the individuals in question only and don't affect its operations.

It's a view supported by some key shareholders. Carina Lundberg Markow, who oversees holdings of Swedish insurance company Folksam, said the latest revelations suggest Fingerprint is "unusually troubled." But she also said her strategy is to focus long term. "It's a question of people, not the company itself. And these are people who don't have a direct operational impact."

Carlstrom denied wrongdoing on Monday. His lawyer Per E. Samuelson said his client has, in interviews with police, "described exactly what has happened, and he hasn't done anything wrong."

As investors learned of the arrests, trading in Fingerprint's shares reached more than double the three-month daily average, with the price sliding 6.4 percent to 55.95 kronor. After having ended 2015 as the stock market's darling (with its share-price gains earning it a place in Sweden's benchmark index), it's fallen from grace more recently. In the past six months, Fingerprint was the worst performer on the OMX Stockholm 30 Index, in part as the sales outlook slows.

The crime authority said it started investigating the share transactions on Dec. 12 after getting reports about abnormal trading. Fingerprint hasn't made any decisions regarding Soderfjell's participation on the board, it said, adding the investigation isn't affecting its operations.

"We take these events very seriously and the information that now has come to our attention," Chairman Jan Wareby said in the statement. "We are of course cooperating with the Swedish Economic Crime Authority."

Soderfjell owns shares through a partnership in Sunfloro, an investment vehicle controlled by Carlstrom, according to Fingerprint Cards' website.