US financial regulators have named more defendants in a case involving alleged insider trading of shares in sports gear maker Reebok International.
Reebok was bought by rival Adidas this month for $3.8bn
"We have named eight additional defendants today," said the Securities and Exchange Commission (SEC).
One of the them is the nephew of a retired Croatian woman accused of insider trading in Reebok options.
Her assets were frozen after "highly suspicious" dealings ahead of news of Reebok's sale to rival Adidas-Salomon.
The SEC alleges that 63-year-old Sonja Anticevic bought call options in Reebok for about $130,000 (£72,000) on 1 August and 2 August.
The next day, the German sports goods firm announced it was buying US rival Reebok for $3.8bn, sending Reebok shares more than 30% higher.
All her call options were then sold, netting profits of more than $2m, the SEC said.
After the options sale, a wire instruction was given to transfer about $870,000 of the proceeds to a bank account in Salzburg, Austria.
The SEC moved swiftly to freeze Mrs Anticevic's account and prevent the proceeds from leaving the country.
Now the US regulator is investigating whether a third party used Mrs Anticevic's name to pull off the insider trade and is switching its focus to her nephew David Pajcin and residents of Croatia, Germany
and the US.
"It seems very likely that someone could have funded her account and made these questionable trades," said Jon Najarian, a Chicago options trader.
The SEC has now been granted a preliminary injunction extending the freeze on Mrs Anticevic's account.
She has denied buying any stock and claims to know nothing about share markets.