MLB commissioner Rob Manfred offered some more insight into the league's investigation of the Houston Astros' alleged electronic sign-stealing scheme on Wednesday. The league has gathered 76,000 emails and talked to 60 witnesses as part of its investigation, Manfred said Wednesday at his Winter Meetings press conference. The investigation will continue into the new year, according to a report published on The Athletic.

After the allegations were made public last month, Manfred announced an investigation into the Astros. The first accusations date to the 2017 season, when the club allegedly used a center-field camera to pick up the opposing team's catcher's signs, and relay the signs to Astros batters. One relay method supposedly involved banging a trash can in the dugout.

Manfred said the investigation would encompass the past three years. 

"I think that this is probably the most thorough investigation that the Commissioner's office has ever undertaken," Manfred said in San Diego. "I think we've interviewed already nearly 60 witnesses, 76,000 e-mails, a whole additional trove of instant messages. That review has caused us to conclude that we have to do some follow-up interviewing.

"It is my hope to conclude the investigation just as promptly as possible, but it's really hard to predict how long something like that is going to take."

The expected punishment for the Astros is unknown and Manfred would not speculate about potential penalties on Wednesday. When the Red Sox were caught stealing signs via an Apple Watch in 2017, Manfred issued an undisclosed fine. He also added a warning to all 30 MLB clubs, noting that any future violations of sign-stealing with electronic devices will be subject to more serious sanctions, including the possible loss of draft picks.