The Boston Red Sox have joined the New England Patriots as the latest Massachusetts team to be involved in a controversial league investigation.

The Red Sox are being investigated for potential violations of the MLB’s international bonus pool guidelines, according to a report from Baseball America’s Ben Badler. Despite being bound by league-issued restrictions due to overspending on international amateurs, Boston signed several top-flight prospects from familiar programs for a bargain cost this offseason.

The league traveled to the Dominican Republic to look into the signings, but some of the alleged methods taken by MLB officials have come under fire for being threatening toward the 16- and 17-year-old players. Various league officials have since denied the claims to multiple outlets.

For those lacking a deep love for professional baseball signings, international bonus pool can be a foreign term. As numerous MLB talents have been discovered abroad, teams invest in foreign-based training programs and establish relationships with said programs and trainers in order to have an advantage when it comes to signing their players.

The MLB allocates these strict pools to each team in the league based off four values assigned to their record from the previous year. International amateurs enter the league as free agents and not via the draft, so the goal behind the bonus pool is to limit the amount of money teams can spend on amateurs yet to play in the league, thus reserving the majority of team funds for investments in veterans within MLB.

Per last year’s Baseball America report, Boston entered the 2015-16 period with $3.7 million in its pool, but the Red Sox, along with the Angels, Rays and Yankees, were serving the first part of a two-year punishment for spending more than their bonus pools in the 2014-15 signing period allowed. As a result, the teams were prohibited from signing players in the pool for more than $300,000.

The Red Sox are now under investigation for attempting to bypass these limitations by signing players to package deals and spreading out bonuses among players to keep their deals low on paper.

Baseball America writes that the team signed two top-25 Venezuelan prospects for $300,000 apiece from Dominican Republic-based training programs the Red Sox had worked with in recent years. Per the website, Nelson Tejada, the MLB’s manager of investigations, recently took a trip with a group of league officials to the Dominican Republic to interview these young players and their training staffs.

The MLB officials reportedly questioned the players individually, sans representation, asking them if they participated in package deals – the commissioner’s office told Baseball America no team has ever been penalized for the practice.

The sessions in the Dominican Republic also included inquiries about whether the players received a bonus meant for another player or moved their bonus to another individual. This practice allows teams currently facing bonus pool restrictions to stay within their boundaries by giving large contracts and bonuses to players outside the pool, and giving the $300,000 standard to those who fall within it. The money is then transferred among these players so as to ascertain proper compensation. It is this diversion that would violate league rules and require league action.

However, methods by which the league officials retrieved the information are allegedly improper, as Baseball America reports the officials told players if they lied, the commissioner’s office would suspend them. They are also alleged to have requested the banking information of the players for further investigation. One source told Badler the players were being treated like criminals throughout the process.

The league denied having threatened players with suspension to both Baseball America, ESPN’s Scott Lauber and the Boston Herald, which cites a league source asserting the interrogation story is one being pushed by those attempting to slide blame to the league. Lauber also writes that league sources say MLB is not attempting to punish the players in this situation and that the Red Sox are not the sole team being reviewed for such violations.

A league official told the Herald that MLB is “right in the middle” of the investigation, making it too early to speculate whether Commissioner Rob Manfred will issue any sanctions. In this case, per Lauber, punitive action could come in the form of fines, suspensions or the loss of future signing rights.