SCOTTSDALE, Ariz. (AP) — Major League Baseball has expanded its investigation into the Houston Astros after The Athletic website reported the team stole signs during home games in 2017 by using a camera positioned in center field.

The report Tuesday quoted pitcher Mike Fiers, who played for the Astros that season, and three other unidentified people with the club. The Astros won the World Series that year — two sources told The Athletic that Houston used the system into the playoffs while another source said the system ended before the postseason.

The website said the process was started by a struggling hitter and a coach, neither of whom was identified. The camera at Minute Maid Park was connected to a television monitor in the tunnel between the Astros’ dugout and clubhouse, The Athletic said, and team employees or players would communicate expected pitches by banging a trash can to signal off-speed pitches.

“I just want the game to be cleaned up a little bit because there are guys who are losing their jobs because they’re going in there not knowing,” Fiers told the website.

The Astros said in a statement the team “has begun an investigation in cooperation with Major League Baseball” and declined additional comment.

Houston general manager Jeff Luhnow declined to talk about specifics.

“We take the allegation seriously and we’re going to look into it. If you’re not following the rules, it’s a serious matter,” he said Tuesday at the annual GM meetings. “I’m not going to get into exactly what I knew or anybody knew at this point. So I’m just going to have to wait and see. But I’m sure there will be an appropriate time to answer that question directly.”

Luhnow said he hoped the allegations wouldn’t put a damper on Houston’s recent run of success, which includes the team’s first World Series title in 2017 and an AL pennant this season.

“Teams are competing with one another and everybody’s trying to find an edge,” Luhnow said. “But we all have to follow the rules and the rules are set by Major League Baseball. We all agree to follow them and if you don’t there’s ramifications to that. We want to follow the rules and we want to compete and win. That’s what every other club does, as well.”

Danny Farquhar, who pitched for the Chicago White Sox twice at Minute Maid Park in September 2017, told The Athletic of ’“a banging from the dugout, almost like a bat hitting the bat rack every time a changeup signal got put down.” He said after Chicago changed to more complex signals “the banging stopped.”

Former Boston Red Sox pitcher Carson Smith added to the sign stealing allegations on Twitter, saying that the Astros bullpen catcher would send signs to certain batters. He added that the “Astros went to extreme measures, undoubtedly still do, and it’s paid off for them.”

MLB strengthened its rules against sign stealing before the 2019 season, instituting procedures attempting to ensure teams did not use video to steal signs.

“After we review this new information we will determine any necessary next steps,” MLB said in a statement.

Los Angeles Dodgers president of baseball operations Andrew Friedman said Wednesday there was “scuttlebutt” that the Astros were stealing signs during the 2017 World Series, but “we certainly did not know anything definitive at the time.” The Dodgers lost to the Astros in seven games.

“There are things that have kind of existed since the beginning of time. And then there are other things that are even more egregious and clearly across the line,” he said. “And I think there are enough people involved in it, it would be pretty brazen to do certain things. And when you do, I think people are going to find out about it.”

MLB already is investigating the Astros. Assistant general manager Brandon Taubman was fired for directing inappropriate comments at female reporters during a clubhouse celebration after the team beat the New York Yankees to win the AL pennant on Oct. 19. The team issued and then retracted a statement accusing a Sports Illustrated reporter of trying to “fabricate a story.” Taubman was fired by the Astros on Oct. 24.

Luhnow said he didn’t think the Taubman situation and the sign stealing allegations are related.

“I don’t think they’re tied together, but they obviously have come one after another it seems like the last few weeks,” Luhnow said. “It’s disappointing. If there is an issue that we need to address, we’ll address it.”